Must Cut the Roots of Italian Cypress to Put in a Block Wall

Q. We are thinking of taking out our wooden fence and replacing it with cinder-block wall.  The Italian cypress trees grow along 2 sections of the fence and are about 20 years old.  The new block fence will go on the other side of the wooden fence but there’s the footing to consider which will cut into the root system.  My question to you is, what are the chances of these trees surviving since we won’t know how much of the root will be cut into?  I can send pictures of the base of the tree with the irrigation and the existing fence post to give you a better picture of the area or I can send measurements of what I am planning.  Not sure if the pictures will give you enough detail to make an informed prediction. 

This is a picture of the soil around some oleanders after a
block wall had been removed and was being replaced. This
is not the readers but a friends. The oleanders were being
watered in a shrub bed with bubblers. Notice that there
is not alot of root development next to the wall.

As you know the trimming of these trees are time consuming and/or expensive to hire out.  We wonder if the block wall will bring more heat to the yard and could the heat from the wall burn the tree?   The reason we are considering this project is that with our dogs we are simply worried that if a plank snaps that our dogs will get out and possibly hurt.  We like to rustic look of the wooden fence but we wonder if the block wall might be a better choice for security.  Any thoughts on your part would be appreciated.
 

A. Let me talk about things I know something about, the damage to the trees if you decide to move ahead with a block wall, replacing a wooden fence.

    In the desert, plants grow where there is adequate water. If a good supply of water is on your side of the fence, the roots will tend to grow more in that direction. If there is lots of water on the other side of the fence, they may tend to grow in that direction.



Notice the difference between the shallow fleshy roots
of the palm tree (left) and the oleanders on the right. Palm
roots grow where there is more air, near the wall.

    So try to picture that your tree's roots will grow more in the presence of water. Would this be on your side of the wall or your neighbor's side? So if a cinder block wall is constucted, a trench will be dug and a footer laid to support this very heavy wall. You are right, this will definitely eliminate a portion of their root system.

   If these tree's roots are growing toward your neighbor mostly, then these trees will suffer significant damage. If your landscape is dry and the neighbor's is wet, this might cause severe damage to your trees.

    If their water is coming mostly from your yard and your neighbor's is dry, hen cutting the roots on the side toward your neighbor will probably have a more minimal effect.

This picture from Washington State University shows
how some plant roots will grow toward a good balance
of air and water such as close to the container wall.

    Likewise if their water is coming from a water source in small amounts from drip irrigation close to the trunk adn the resest of the yard is dry then the impact will probably  be minimal. In other words,if you are trenching in soil that stays dry for most of the year you will probably be okay.

    Another word of caution. The week before they put in the footer water the trees very well. Then let the soil dry out until they dig. Encourage them to dig, put the footer in and backfill the soil as soon as possible to minimize damage to the trees. As soon as possible, irrigate the trees again.

What Kind of Grass Do I Have?



If you see this on your sidewalk you have
common bermudagrass either
as a weed or as a lawn grass.

Q. We moved here last year and have not ever had the experience with the type of grass that is in our back yard. My husband says we need a four wheel drive lawn mower for mowing, extremely bumpy and patchy. What kind of grass seed should we be using here for this environment, and when to re-seed? Thank you and the Gazenias you advised me to plant and thick and healthy!!

A. It will be tough to tell but the two common grasses here are fescue (a bunching grass which might be giving you all the bumps) and bermudagrass. Bermudagrass runs along the ground and is flat. The bermudagrass, if that is one you have, will turn brown this late fall and early winter (November/December).

If you have a mixture of the two then you will see the parts of the lawn with bermuda turn brown this winter and the tall fescue will stay green in clumps. If you do have a mixture it is usually because of an inadequate irrigation system or not very good irrigation practices. The bermudagrass can survive with lots less water than the fescue. So when water is limited, the bermudagrass takes over those areas.

From left to right upper leaf surface of Kentucky bluegrass,
perennial ryegrass and tall fescue. Actually the tall fescue
leaf surface could also pass for annual ryegrass.

It is easy to spray and kill the fescue during the winter in the bermudagrass (beremudagrass is brown then and sleeping and will not get hurt) with Roundup but not the other way around. But most people do not like a bermudagrass lawn. Hope this helps.

Overseeding Bermudagrass With a Winter Grass

Q. My backyard has a bermudagrass lawn and I would like to overseed with a winter ryegrass seed. When I have done this before, I "burned out" the bermuda by not watering it, then rented a power rake to de-thatch it. This year with all the rain, my bermuda is not turning brown. My concern is if the lawn is green the power rake will not remove the thatch. Also, which do you recommend annual or perennial rye seed and why?

Dethatcher or verical mower.

A. Overseeding bermudagrass with a cool season grass like one of the ryegrasses has a window of time which is optimum in the fall. This window is from September 15 to October 15. If you overseed to early, the bermudagrass is too active and will compete with your winter lawn. If you overseed too late, you run the risk that it will get too cold quickly and the overseeded grass may not all germinate and fill in your overseeded area.

            The mantra for effective overseeding is having “good soil to seed contact”. In other words, the seed should rest on the soil when you overseed correctly. If the bermudagrass is too dense, much of the seed will not land on the soil and you will have a spotty winter lawn.

Common Bermudagrass stolon

            Sounds like you have the correct sequence for overseeding; time the overseed around October 1, September 15 turn off the water to the bermudagrass, September 21 mow as short as possible (rotary mower on the lowest setting is fine), power rake or dethatch until you see bare soil, apply seed, fertilizer, topdress the seed and fertilizer and water.

            Bermudagrass lawns are usually mowed somewhere from ½ to 1 inch high. I like to let it grow to an 1½ in August/September. This produces more stem so I can “scalp” it better and get the seed to fall onto the soil for that good soil/seed contact.

            You can use annual ryegrass if you want but it is coarse textured, light green and rough to the touch. Perennial ryegrass is a much prettier grass and soft to the touch. You can put all the nitrogen you want on annual ryegrass and it will just not get the same dark green color as perennial ryegrass. It is more expensive but will give you a much prettier lawn.

Vine in Lawn Turns Out To Be Bermudagrass

Q. I found this vine growing in my lawn and sent you pictures of it.  I tried treating it with Ortho's Weed Be Gone.  As of this morning I still have the vine.  Do you have any idea what it may be and how I can treat it or get rid of it?

Vine in lawn appears to be bermudagrass
or Devil grass.

A. From the look of this "vine", it appears to be bermudagrass. Some old timers call it Devil grass mostly because it is the devil to get rid of. Once it is in a lawn, it is tough to nearly impossible to get rid of.

            It is easier to get rid of if it is in a shrub bed. Then you can cut it back to a foot long (as long as it has leaves) and "spot spray" what’s left with Roundup. Other products that have reasonable success at some control include Poast and Fusilade which can be used fairly safely among shrubs and groundcovers.

            Bermudagrass gets in a lawn usually if the lawn begins to "thin" or lose its density. This is because it is not kept full and dense. This can be because it is not fertilized regularly, mowed too short or an insect or disease problem.

            Mowing too short can occur by lowering your mower too close to the ground or by using a line trimmer and whacking the grass low around sprinkler heads or along the edge of the lawn to make it look pretty.

            The best defense is a good offense. Keep the lawn at 2 to 2 1/2 inches if it is fescue. Keep it fertilized regularly. If patches of the lawn die, do not disturb the dead area and/or reseed or resod until mid to late September when bermudagrass is going to sleep.

Bay Leaves Browning and Yellowing

Q. I have several bay leaf bushes but one appears to be dying.  What can I do, if anything, to nurse it back to health?

A. Two things are going to be a problem for you, maybe three. First, judging from your picture, it is in rock mulch. This plant will not handle a rock mulch environment very well. If it is going to work for you in rock then it should be in an eastern exposure where the wall would be to its west.

Picture will not insert properly in Blogspot. Bay Leaf of reader.

            If your plant is in this environment then it might be getting hammered by being fully exposed to the southern sun as well. It will do much better with some protection from that hot, blazing sun in the summer. That is why you are seeing the leaves with brown tips and edges.

            Secondly is the yellow color developing on the new leaves, leaves at the ends of the branches. Most likely this is a nutrient deficiency due to the poor nutrient capacity of that desert soil. Rock mulch adds nothing to a desert soil. It needs a more fertile soil and should not be planted like it is growing in the middle of a desert somewhere.

            Thirdly, you might have trouble keeping it through the winters here. It is not terribly tolerant of real low winter temperatures. If it is in the open and can get hit by cold winter winds then it may freeze back yearly or every few years when we hit a good cold spell.

            I would move it to a new location this fall, about mid-September to October. Move it somewhere where the sun won’t hammer it after noon or two PM. Heavily compost the soil when you plant it. Use organic mulch around it, not rock mulch. Put it somewhere the plant will be protected from freezing winter winds. Hope this helps.

Lack of Fullness in Japanese Blueberry

Q. I was referred to you by Lori, a Master Gardener re: my problem with my Japanese Blueberry trees. I have planted 3  in November 2009, they are about 7 ft tall, 4 ft wide, trunk column about 3 inches in diameter . Leaves seemed to fall prematurely, browning and yellowish. One of the trees bark is peeling off and appeared to be dry. I have 3 sprinkler tubes on each tree, dripping 1 gl/hr each (I think). There's no visible insects but I do not know what to find anyway. Leaves seemed scarce, does not have that fullness that other trees does.  I have not sprayed them anything, no fertilizer or some sort. I put some manure compost 2 months ago. I am a novice on gardening so my description might seem funny. I can send some pictures if that would help. I have spent so much money on them for them to die. Please help.

Japanese blueberry along a block wall in rock mulch

A. Japanese blueberries will require a soil that is a composted at the time of planting and an organic mulch on the surface of the soil after planting.  It will do terribly in south or western exposures in full sun or in rock mulches.  If you planted this Japanese blueberry from a 15 gallon container then it will require about 15 gallons of water each time you water.  

The amount of water must increase from this amount as the plant gets larger from year to year.  This can be accomplished by adding minutes to your existing irrigation schedule at each watering or adding additional emitters.  If these are 1 gallon per hour emitters and there are three of them then the irrigation run time for this tree should be somewhere around 5 hours for it to get adequate water.  

Water requirement curve for the Las Vegas area. The first bar (1) is January
and the last bar is December (12). You can see that water demand by
plants increases 400% from January to July and August.

Unless this plant is getting water from other sources it will be under watered if you are irrigating for only one are 2 hours.  The frequency of application of the water, but not the number of gallons per application, will vary from season to season.  There is generally are a winter schedule, spring schedule, summer schedule, fall schedule and back too a winter schedule which means you should increase the number of times you irrigate per week about four times each year.  

These schedules will coincide approximately with December 1, February 1, May 1, mid June, mid September and finally December 1 which completes the seasonal cycle.  

Because your plant does not have the fullness that caught your eye I would assume it is due to improper irrigation which may have led to infestation with borers.  Pull off the loose bark at you see and look for damage in the wood do too boring insects.  This would include sawdust under the bark and perhaps elliptical exit holes from the trunk under the damaged area.  If the damage is more than half way around the trunk then I would replace the plant.

Yellowing on Meyer Lemon Might Be Magnesium Deficiency

Meyer Lemon with deficiency

Q. We have went to the nursery a couple times about this tree. First we got the water cycle correct, then iron was suggested which we did as they directed then Gold Dust was suggested. Online I read possibly the tree suffers from a magnesium issue. I thought these photos would give a better picture. All we did as directed and the tree is not responding in fact it is getting worse. I am wondering if it is because of where it was planted which is a confined root growing area. Any insight would be appreciated.

Meyer lemon another shot.

A. By looking at the leaves I have to assume this is a Meyer Lemon (which is, by the way not technically a lemon but an unknown hybrid found in a Chinese back yard by USDA researcher D. Meyer in the early 20th century). Your pictures are all pretty good with the exception of not showing a critical view of the trunk where it is just out of the soil. Just for future reference always look at and show this interface of the trunk and soil. W/o that view I have to only guess that the rootstock/trunk union is well out of the soil and we can eliminate that issue. And, a shot of the soil might show how the plant is getting watered. I have to assume drippers and I would guess they are in the same locations as when the plant was planted.

The leaves show two distinctive symptoms that often occur in concert: 1. There is some salt burn and 2. The common symptom that comes with salt issues is the magnesium deficiency. Just FYI Iron def. only occurs on the new leaves.

For the salinity (salt) issue we usually look first at the watering and with watering comes knowing if the water can even be applied uniformly all around the edge of the canopy, sometimes called the 'drip line'. Citrus are botanically a shrub with shallow and wide spreading roots that are tough to grow to maturity with drippers unless they are closely spaced in a wide band around the canopy's edge. There is one picture showing the plant is right next to a step wall with no water being applied in that zone of the root system.

I would not worry too much about adding any supplements and see if you can begin to manage a watering system of application that would give a long deep soaking water application out near the drip line. The 'soaker' hoses could be laid out on the ground out near the drip line and let it run for hours and hours to try and leach out the excess salts that may have accumulated over time with the drip system. Drip systems are fine but, due to their limited water output salts can begin to accumulate thus impacting citrus' sensitivity to salts.

Give it a long deep watering about once every few weeks from now on all during the growing season (May through October)  to supplement the regular water to leach out the salts that inevitably are deposited with the limited volume of drip systems . .This leaching watering is also the great time to add fertilizer and get it into the soil evenly all around the active roots near the drip line.

Terry Mikel

Gardener Moving to Las Vegas from San Francisco

Q. My husband found your site. We are facing the possibility of a move to Las Vegas. We have never lived in a desert climate. I am hoping to continue my love of gardening with vegetables, flowers, and a water garden like I have here in the San Francisco Bay Area. My biggest problems here have been raccoons, squirrels, aphids, and powdery mildew. Will any of those be things I will face in Vegas? What are the biggest pests/problems I should prepare for? (I'm praying you don't say scorpions or fire ants!)

            Also, my great love is dahlias. I have about 44 plants here, though ironically our summer was so cool that it was a poor year for us (our tomatoes were also a disappointment, and I sure hope that won't be the case in LV). How well to dahlias fare in Vegas, and will they bloom at a different time of year? Should I consider putting them in double pots and not in the ground (we've talked about raised beds with high quality soil)? Someone told me that grasshoppers are so bad there that I will need to completely fence in the whole garden area with small mesh wire to block the bugs out, is this true? What are your thoughts?

            I realize this letter contains a lot of questions... but any help you can give a life-long gardener or who very nervous she will have to give up all the plants she loves would be greatly appreciated

A. Well Shannon... we do have bark scorpions but we don’t have very many fire ants. Those are pretty rare and relatively easy to control so far. So take a deep breath... it’s not so bad. The desert can be beautiful.

            No raccoons in the Las Vegas area. No grey squirrels but we do have ground squirrels which some call chipmunks which they aren't but they do look a little like Chip and Dale. They can be pesky.

            We do have some aphids in the spring but they disappear when it gets hot. Powdery mildew is relatively rare compared to San Francisco. Dahlias will be tough for you in Las Vegas. We can produce some wonderful vegetables and fruits here and you will find them rivaling in quality to what you can find at the Farmers Markets in San Francisco.

Ground squirrel

            Now the bad news. This is the desert. Growing things here will be NOTHING like what you are familiar with. You will have to relearn your gardening skills and adapt them to the desert climate. Your new mantra will be compost, compost, compost. And everything will revolve around water.

            Yes, you have a lot to learn but think of it as an adventure and your gardening skills will be tested here. No "throw a seed in the ground and watch it grow" here. Thats why I am here. Feel free to ask. By the way, the grasshopper story is totally far-fetched. You will need a shotgun. (Just kidding, it is not that bad ......... most years) :-)

Maybe some others here can give you some pointers.

Rock Mulches Not Bad But Present Problems for Wrong Plants

Rose growing in rock mulch.

Q. I have moved into a house that is about 3 years old with a wide variety of plants.  I have read your articles against rock mulch but I don't know which of my plants can tolerate the rock mulch that is already there and which ones I should pull the rock away and use wood mulch.

            I come from Northern Utah and do not have a clue how to handle these types of plants and all this rock.

A. I am not against rock mulch but it should not be used for everything and not all plants should be planted into rock mulch.  My personal philosophy on desert landscapes focuses on using appropriate mulches for plants which can tolerate those mulches. 

            Generally speaking, those plants which originate from arid or desert environments can generally handle rock mulches.  Those plants which do not originate from arid or desert climates probably should not be planted in rock mulch.  There are always exceptions which never help when you are trying to make rules.

Photinia growing in rock mulch.

            The problem is that we intermingle desert plants with non-desert plants and then we use rock mulch around everything.  Those plants which can tolerate the rock mulch end up, over time, to do all right. 

            Those plants which are not true desert plants tend to decline and fail over time.  Plants such as bottle brush, photinia, Carolina cherry laurel, Japanese blueberry, butterfly iris, mock orange, and others usually begin to decline in 4 to 5 years after they are planted as soil amendments used at planting are depleted. 

            If you want to learn how to handle nondesert plants in rock mulches please visit my blog and search this topic.

Bottlebrush growing in rock mulch.

            The other reason for decline would be improper watering.  Make sure you get your irrigation intervals and the amount that you apply each time to be adequate for the plants.  Improper watering will cause plants to look terrible as well.

I Want to Plant a Necta Zee Nectarine. Will it do well here?

Q. I want to plant a necta-zee nectarine tree. will it do okay in Las Vegas? I looked on your fruit tree list and it shows its under review.

A. You are right it is under review. It is expected to do very well but to date it is only about three years old so it is very new for us. I like to see about three years to five years of production before I determine how it will do in southern Nevada. It is a Zaiger Genetics release I would expect the fruit will be good to high quality. Watch for thrips damage to the fruit (scarring) in the future if you plan to go ahead with it.

Necta Zee Nectarine

Preventing Weeds From Growing on Top of My Weed Barrier

Q. Weeds that infested an area of my yard - there is a screen like barrier just under the top soil. My question is what can I do to prevent this in the future without killing the shrubs in this area and what is the best method to eliminate the weeds that do emerge. I pulled and dug these and don’t want to have to do that again in the future.

Weed barrier or geotextile under nursery containers to
prevent weeds from growing

A. I am assuming the screen like barrier may be a geotextile used to prevent weeds that might germinate and grow up underneath and through it. These are frequently laid on the soil surface with a 2 to 4 inch surface mulch applied on top of it. The surface mulch helps to shade the barrier and prevent the germination of weed seeds beneath the barrier. We do not use sheet plastic for this purpose. That is a huge no-no which is another topic in itself.

Weeds such as bermudagrass and nutgrass can grow through the barrier and the mulch but it can be very effective in preventing other weeds. If bermudagrass and nutgrass weeds are close to a source of water such as a drip emitter or a leaky hose they will have no difficulty growing through the barrier and through the mulch.

Weed barrier down. Lets air and water through to the soil.

The other problem with textile barriers covered in mulch is that windblown dirt is trapped by the rock mulch and falls on top of the textile barrier. Over time, this windblown dirt accumulates and forms a soil layer on top of the textile barrier in amongst the rocks. Weed seeds then blow over the rock mulch or might be carried by birds where they fall between the rocks and onto the soil on top of the barrier.

If there is rain or a source of water, weeds will flourish and the textile barrier appears to fail. The barrier has not really failed. The accumulation of windblown dirt on top of the barrier is a major culprit. Weed seeds below the barrier are still prevented from penetrating the barrier and making it to sunlight.

Geotextile barrier

There are three things which you can do to help prevent weeds from getting established. The first is to make sure your sources of water are limited to only where the plants are growing. If you have water that is spraying onto the rock mulch or puddling into open areas from other sources than you are going to have problems. It is imperative to make sure water is contained in the area where plants are growing.

Secondly, it is best that mulches are deep. A 4 inch layer of mulch is much more effective at controlling weeds than a 2 inch layer. Coarse mulches are more ineffective at controlling weeds than fine mulches. By a coarse mulch I mean rocks that are at least 1 inch in diameter.

          Thirdly is the point you are probably not going to like and that is staying on top of weed growth. We have an old saying as gardeners that basically says one year of weeds leads to seven years of weeding. This just means that if you fail to control weeds in your garden area and let them go to seed then the seeds released by these weeds will lead to seven years of weeding.

It is so very important to stay on top of your weeds and get them removed before they form flowers. There are several types of garden hoes that are very effective. For bare soil or very fine mulch I like the diamond hoe. For larger mulch pointed hoes or even a shovel works well. If the weeds are relatively large, spraying the area with water from a hose and hand pulling weeds about 15 minutes later is very effective as well.

Black plastic when laid under rock starts to poke through
in a couple of years. Very ugly. Black plastic is a
temporary mulch and rock is a permanent mulch.

          To aid the gardener chemical companies have developed weed killers that can kill seeds as they are germinating or kill the plants after they have grown from seeds. Many of them are very effective however you are applying and unnatural chemical which is potentially, and in varying degrees, dangerous to other plants, animals and our environment.

          Check with your local ordinances but there are devices which use fire to control weeds. These frequently operate off of LP gas with some sort of torch. These are also potentially very dangerous and should be used with extreme caution.

          In a nutshell, there is no magic bullet except to make sure water goes where you needed to go, increase the depth of your mulch layer and stay on top of your weeds and do not let them go to seed.

Which is Better? Miracle Gro or Compost?

Q. Compost or Miracle Gro? Which is better?

A. No question that good quality compost is usually the best choice. Problem is finding a good quality compost and using it appropriately. Good quality composts are expensive.

            There are potential problems with compost. These include unwanted salts that can come with the compost, its potential problem with food safety issues like E. coli and other microorganisms that accompany the use of manures, the development of some insect problems such as fungus gnats and grubs and potential weed problems if the compost was not handled properly.

Yellowish brown leachate (liquid) from the compost.
A compost tea full of lots of stuff.

            High quality agricultural fertilizers can be big help in our landscapes. They can be applied to the soil and usually to the foliage as well. They can supplement a good fertilizer program whether you use compost or not. I will talk more about this on my blog.

 

fecal matter safety compost -

Trees Growing But Lacking Leaves and Not Full

Crepe myrtle lacking leaves

Q. I am one of your long-time readers and fans. I am attaching pictures of four different trees from our backyard in Queensridge (basically Summerlin) that seem to be challenged.  In each case, the tree is definitely alive, but simply lacks enough leaves – or so it seems to us.  All of the trees have received plenty of organic matter, fertilizer (possibly not enough, fish and iron chelate is what they get), water, and all are mulched in with organic mulch (compost under-layer and wood chips on top).  The backyard faces North and West and, as you can see, is quite open as it is surrounded by a golf course.  Why are there so many naked branches, weak-looking leaves, and not enough leaves?  Thank you for your help. 

A. Thank you for the great pictures and breaking them into two emails. That helped quite a bit. Here are some comments on what I saw.

First general comments. The plants are actually doing quite well, maybe even a bit too well. There is plenty of new growth which is what you want but because they are so “happy” they are growing very quickly and thus you are getting big spaces between leaves and buds. This results in an “open” appearance.

Persimmon tree with open appearance

Many of your plants, now that they are getting lots of nutrients, water and in a great growing condition are now growing as fast as they can. This will result in larger plants that will start to flower or fruit further and further from the ground as they get closer to their mature size. Plants do this naturally because in nature they are always competing for sunlight and other resources that keep them alive.

How do slow them down? We focus on two things: reduce those “goodies” they are getting that encourage a lot of growth (water, fertilizer) and (this next part is harder to realize a bit) get the plant to reduce its own growth in each of its growing branches by increasing the total number of branches it has to support. This then causes the “goodies” that encourages growth to be divided up among many more growing points and slows it down. It’s like having an income of $50,000 a year and having to support three children or 20 children; your resources are divided up many more times  so each “child” gets less.

Generally speaking, reduce “goodies” by reducing your watering frequency (how many times you water per week if possible) and cut your fertilizer application in half (but not to the point where it is starving or gets leaf scorch) and (increase your children) prune. The type of pruning you will mostly do this winter will be what I call “heading cuts” rather “thinning cuts”. Heading cuts increase the total number of shoots in a tree while thinning cuts typically do not. If you want to see the difference, please visit my Youtube video on this subject

http://www.youtube.com/watch?v=yKDSzCfvqe0

Now your individual trees, you must decide what you want for the ultimate height on these trees. If you want them to be large (such as flowering trees for beauty, shade or screening) then let them go and don’t do much pruning. If you want trees to be smaller and more compact (fruiting and harvest for instance) then you will cut them back pretty hard and take away from them their luxurious growth. You will prune these trees twice each year; once in the winter and again (taking away new fast luxurious growth) in April (summer pruning).

Magnolia with open canopy.

Crepe myrtle. I would assume you want a larger tree, perhaps with multiple trunks (3 to 5) coming from the ground. Don’t reduce the height. Let it go. Pruning will focus on removing dead, twiggy growth (it has lots of these due to flowering) and use thinning cuts to eliminate branches growing too close together, one branch growing on top of another, branches crossing each other, etc.).You can reduce the height by making thinning cuts and removing the tallest limbs and branches back to a “crotch”. I would not do much of this until it gets closer to the height you want it to get. You will fertilize in January with an all-purpose soil applied fertilizer such as 16-16-16 or even a rose fertilizer. You will see benefits from adding iron chelate to the soil in January and foliar applied fertilizers such as Miracle Gro about two or three weeks after the leaves emerge in the spring.

Magnolia. This is another tree you could elect to let it grow. Having a multiple trunked tree will help to keep it smaller. You realize that this tree is not a terribly good choice for our climate so you will spend more effort and money on this tree than many others. It will need the mulch which you are doing. This will give it some soil improvement near the soil surface as it decomposes. It will require a fertilizer application in January to push new, healthy growth. It will also benefit from an iron chelate. It will not most likely need a foliar fertilizer but it will not hurt it if you chose to apply it in February or March. Your choice but it might do better if it is kept smaller than the mature height it will try to reach. Perhaps if you can keep it in the 25 to 30 ft. range it will be easier to keep healthy. Perhaps saucer or star magnolia might work better in the future. Not as pretty but still pretty. There is a southern magnolia called Little Gem that is smaller.

Persimmon. Cut this tree back hard if you want your fruit closer to the ground. Your tree is too lanky. Cut back into older wood about half way in where it is too long in late January or early February. Don’t be afraid to do this. It will handle the hard cuts. Fruit is produced on current season wood so it will flower and fruit from new growth.

Young Apricot Leaves Drying Up and Liquid Oozing

Q. I planted a Blenheim Apricot in March.   At first it did not seem to take but within four weeks it began showing growth whereas all the other fruit trees took almost immediately.  Its been doing fine until just recently when I noticed some of the leaves on the main truck were drying up.   I check the moister level regularly.   Looking closer at the graft there seems to be some liquid oozing out.   Enclosed are some photos of the liquid, drying leaves, and tips of higher leaves.   Any thoughts on what I’m up against.   Rootstock is Citation Hybrid if that helps.

All my other fruit trees planted in the same general area are doing just great.

Iron chlorosis, inter veinal chlorosis, or yellowing
between the veins typical of new growth when iron
chlorosis is present

A. Some great shots and I would like to post them on my blog. Your photos tell a nice story I dont get to tell very often. But first lets look at the obvious and the is the discoloration of the leaves.

The yellowing between the veins is called "interveinal chlorosis". Chlorosis just means "yellowing" so it is yellowing between the veins. The most common reason for this in our alkaline soils is nutritional and frequently it is a lack of iron. Other nutrient deficiences that can cause similar types of chlorosis can include manganese and zinc deficiencies. I would guess this is an iron problem.

The picture of the sap at the place where the rootstock (in this case Citation) meets what we call the scion (in this case yours is Blenheim apricot) we see some damage. It is very close to the bud union or dogleg (where the two meet).

Bud union or dogleg. Where the Blenheim apricot was
budded or "grafted" on to Citation rootstock and sap

The damage may have started at the time of planting and is most likely from sun damage or sunburn. This area should have been painted with whitewash or any diluted white latex paint. Dilute 1:1 with water. Or you can put anything in front of that area that would give it some shade until the tree puts on some canopy and shades itself. You can use wooden shingles, cardboard, anything to cast a shade on the trunk.


Usually, if the trunk gets sunburn then it is highly likely it will also draw borers to the damage and you will get borer damage there. It is very likely this is what you are seeing. YOu can find out easily by bending the canopy of the tree over. If the trunk breaks, it will break at the borer damage and you will most likely see them there. If it does not break when you bend it, it may just be sunburn. If the sunburn is not extensive, it is posssible it could heal itself but rather unlikely. You may have lost the tree.

Interestingly, this dunburn and damage at the dogleg can also lead to the chlorosis or yellowing of the leaves as well. The sunburn damage can interrupt the flow of nutrients including iron up the tree and the interruption may be enough to limit the supply of available iron and lead toward iron chlorosis. However, some iron chelate sprays on the leaves a few times, along with a teaspoon of Ivory liquid per gallon of spray, may be enough to green the leaves up. I would guess 4 to 6 applications made in the wee hours of the morning when it is cool.

Next time whitewash the trunk at the time of planting or provide some shade on the trunk until the canopy gives enough shade to protect itself.

Snake Squash Growing in Mesquite Tree Not Fruiting

Q. This is the second year I planted Snake squash. As you can see by the attached picture they are very healthy and happy growing up my Mesquite tree. Last year I tried growing them in my garden and had the same problem, beautiful plants and no fruit. The blossoms appear, open then shrivel and fall off. What am I doing wrong?

A. I think you are always going to have problems with any plant that produces vegetables from flowers when it is growing in such low light levels with so much shade. Vegetables that you grow for their leaves do not require very high levels of light but vegetables grown for something they produce from their flowers usually requires much higher light levels.

If flowers do appear, try to discern the difference between male and female flowers. Like most squash, male flowers come first followed by female flowers. The female flowers need to be pollinated either by hand or by insects. If bees are few and far between then this may be a problem. Also they have a tough time setting fruit at high temperatures. All or any of these might be a problem for your plant.

I would recommend that if you want a vegetable that you consider enriching the soil and try to orient the plant so it gets a minimum of six hours of full sunlight. The of course  you want to fertilize it so that it can handle this type of production.

Leaves Burning Up on Cherry Tomato Plant in Container

This is not the readers tomato plant. These
are some leaf spots on tomato that were
never identified but probably diseased. Make
sure your leaf scorch is not a disease problem.

Q. Hi, I just read your gardening article in the Summerlin South View paper and thought I would take a shot at sending you an email with some concerns I have with my tomato plants. I moved down here a year ago from MN and was an avid gardener up there.  Down here?  It's a different story.  I have cherry tomato plants on my patio.  Not always in direct sunlight, but I water every day.  They seem like the leaves are burning up on the plants and the fruit has tapered off.  Any suggestions or ideas?  If you aren't able to answer this, can you point me int he right direction please? 

A. I dont know how you prepared your soil for the container but that is important. So make sure it is a good quality soil if you prepare it yourself or buy it in bags. Tomato production tapers off when temperatures consistently stay above 95F. Tomatoes and many other vegetables do not set very well under high temperatures. As temperatures drop, they will begin to set again.Vegetables that set fruit will need at least 6 hours of strong sunlight every day.
 

Morning sun is preferable to afternoon sun because usually afternoon sun also means a hotter microclimate. Direct sun on containers can fry a soil, particularly if the container is small, single-layered, dry when it gets the direct sunlight and dark colored.

I would double pot containers (one container inside another) to help reduce direct sunlight on the growing container. Put the plants in direct sunlight in the morning hours, make sure you use a good soil each time you plant and modify it with good compost.

Cukes Yellowing and Deformed and Beans Not Producing

Royalty Purple Pod Bush bean growing at The Orchard

Q. I am a fan and follow your column religiously. I have planted a garden for the first time this year. Out of three tomato plants two gave a good yield, the other had blossoms but nothing. The cucumber plants are growing like crazy, and have a bumper crop of cukes, but now they are turning yellow, and some are deformed. The leaves are turning yellow, and there are hundreds of these tiny little flies all over. I have sprayed with water but they come right back. The string beans have tons of blooms, but no beans, even though the vines are growing like crazy. My dill didn't make it. I have some sorrel, and the basil did well. My strawberries gave three or four little berries, and that was about all.

Dragon Tongue bush bean growing at The Orchard. Very
susceptible to crown rot by the way.

            I need and would like to take some classes, if I could find the time, but my husband has dementia, so I am kept quite busy. If you could shed a little light on my problem I would appreciate it. Do you think I should tear it all out, and start to get ready for Fall planting?

A. I am sending you a copy of Sylvan Witwer’s vegetable production book. He was retired from Michigan State University and was a celebrated horticulturist and vegetable scientist living in Overton, NV, after retirement. He has since moved to Utah.

I would read through this and follow his planting guide for time of year for planting things. It is pretty hot right now for alot of things to set fruit. Many have trouble setting fruit when tempertures top 95 to 100F. Your beans are out of season now.

Start ripping out the things that are not producing or producing pooly. Reamend those spots with compost, a GOOD compost. Good composts are expensive. Use a preplant fertilizer at the time of planting  high in phosphorus and mixed with the composted soil where you plant. If you are organic, use bone meal or equivalent high in phosphorus.

Variety selection is important. Record which varieties worked for you and which did not. If you plant at the right time, your beans and cucumber production should be better.

Crooked cucumbers. Generally, misshapen fruit are the result of stress or poor pollination. Poor pollination (cukes require about 8 to 10 visits by a bee) result in crooked cucumbers. However, fruit shaped like a lady's figure may be the result of drought during its development or not enough visits by bees. As temperatures get hotter, bees are less efficient as pollinators. They spend alot of their time and energy trying to cool down their hives or homes. We have to rely more on our native pollinators like the leafcutter bee.

 

So poor pollinations can cause crooked, misshapen and yellow cukes to form. As temperatures drop and if you keep your plants alive and healthy, you should see your production pick up again. However, replanting cukes from seed will also work and then you get the advantage of having younger, more prolific plants.

As far as your "flies" are concerned, I am not sure what they are or if they are causing problems but if you feel they are then usually frequent applications of insecticidal soap like Safers can reduce pest problems if sprayed directly ON the insects. This means spraying UNDER the leaves as well as on top of the plants. Never spray plants when they are in bloom unless it is at dusk or a few minutes after sunrise.

Asparagus Crowns Not Covered Deeply. Bury them now?

Asparagus started in a trench from seed and
on drip irrigation at The Orchard

Q. I planted asparagus crowns in March at at depth of 12 inches. They are in a pit and my plan was to cover the shoots with soil, an inch at a time, as they grew. Well, they grew rather sporadically so I didn't want to inadvertently bury a new shoot...so I never backfilled the pit to the level of the surrounding soil. Currently, I have about five shoots (out of 12 crowns) that have ferned. The crowns are about two inches underground and about 10 inches below the level of the surrounding soil. Is it OK to backfill the remaining 10 inches at this point? Or would that damage the plants? On the watering, there's no set schedule. Just keep the ground moist, but not too damp, at a certain soil depth, correct?

A. I would slowly add the soil over time up to the correct level. The problem you have now is that the crowns have adjusted to this soil level and I would be worried that completely covering the crowns might damage what you have already. When you begin to backfill, mix in plenty of compost with the soil you are using for backfill.

Asparagus started from seed and the trench
is all filled in. The asparagus spears are not
harvested the first year from seed. Spears
are allowed to grow and fern out to help
get the crowns established.

Dont just use desert soil. Make sure the soil is loose and can drain easily. Remove any large rocks so that these rocks do not cause the spears to emerge damaged or interfere with their emergence. Part of the sporadic emergence, I would guess, would have been your watering or how the soil drained. Asparagus loves to grow along streambanks or irrigation canals. It is an oasis plant so to speak and loves the same environment as palms, grapes, figs and even pomegranates. I hope this helps.

Prune Out All Dead Areas of a Bottlebrush?

Q. I have a Bottlebrush shrub with a dead area. My question-What would be the best course of action to improve the condition of this shrub, pruning out all dead areas, then cutting it back?

Bottlebrush

A.  On your bottle brush I would guess this is either lemon or Scarlet bottlebrush. Depending on the bottlebrush it can get anywhere from 15 to 25 feet tall. You can train it as a large shrub if you want or small tree. This is an Australian plant that is not really considered a desert plant. However, they are typically fairly drought tolerant which just means they can survive periods of time with little water and recover when water is reapplied to them in sufficient quantities.

They don't particularly like desert soils and have a tough time in our alkaline soil environment. For this reason they tend to go yellow which is chlorosis most likely from a lack of available iron. They also would rather be growing in soils heavily amended in organic material such as compost at the time of planting. They will also grow better in a wood mulch, not rock mulch.

To correct iron deficiency apply an iron chelate to the soil in early spring or late winter. You can do it now and still get some response from it. The best iron chelate for the job is iron EDDHA (check the ingredients label on the label). You can spray the foliage with an iron solution several times and get a similar result but the soil application is much more ineffective and efficient.

Another bottlebrush showing extreme chlorosis in rock mulch

You will have to do this every year particularly if you continue to grow it in bare soil or rock mulch. This plant should be fertilized in January with an all-purpose fertilizer for trees and shrubs as well.

You should make a determination about whether you want it to be a shrub or tree. I like them better as small trees. If you decide to keep it is a tree then prune at the soil level so that you have 3 to 5 major trunks originating from the soil surface. Remove everything else and keep that area under the tree free from new suckers. Remove any broken or crossed limbs.

After you have fertilized this tree with an all-purpose fertilizer and iron for the next two years, then begin to work on developing the architecture of the trees canopy.

Early Mid and Late Peaches for Season Long Production

Q. I live in the Mesquite area (1800 ft elevation) and was looking to plant 3 differant varieties of peach's that would not ripen all at the same time. Would also appreciate some advice on when to plant them and where I might obtain them should you recommend bare roots.



The eye-popping visual of Indian Free peach. Flavor is
incredible as well when it is grown in the desert.

A. It is hard to predict which peach trees will be available for you to purchase to help you plan. I can make recommendations but these trees may or may not be available.


Off of the top of my head, I would probably pick a yellow peach, a white peach for sure. Something like May Pride, Babcock and Indian Free. If you look at my downloadable recommended variety list it will tell you which are early, mid and late peaches.

http://xtremehorticulture.blogspot.com/2011/10/recommended-fruit-trees-for-southern.html

You can also look at varieties posted on Dave Wilson Nursery at

http://www.davewilson.com/br40/br40_trees/peaches.html