Harvested Hard Peaches Will Ripen

Q. I just picked all these because the birds were getting them. Will they ripen enough to eat?  I covered the others with netting that are still on the tree   Do I need to put them in the sun or in brown paper?

A. Pick them! They will ripen at room temperature in 2 to 4 days I would guess. If you can keep the humidity up in some way it will reduce their water loss. 

But keep them at 65 to 80F if at all possible and out of the sun. They do not need to be in paper bags. Once fully ripened you can put them in the fridge.

Peaches Can Be Harvested Early

Q. Can I pick peaches when the color starts and will they ripen?

A. You can pick peaches when the color begins to change from green to yellowish green or even beyond. I prefer to wait at least until the color has solidly changed from green to yellow but are still firm.

Peach fruit with color breaking from green to red. They can be harvested at
this stage and they will ripen but the quality will be lower than if they were
left to ripen to a more mature stage on the tree. Birds are not yet interested in
them at this stage.

At this stage they will continue to ripen after they are harvested if they are kept at room temperature. They will develop better flavor if left on the tree as long as possible. If birds are not a problem then I prefer to leave them until the fruit has changed color and the flesh has softened just a little bit from being hard as a rock.

At this point, the birds are looking at them and not quite sure if they want to peck them or not. This is the stage also when some of the more hungry birds will peck at them anyway. When I first start to see bird damage I know I’d better get them off the tree.

What Causes Apricot Fruit to Drop?

Q. I've had my apricot tree about 15 years. Last year it had a huge crop. This year it had lots of blossoms, swarms of bees, but almost no fruit set. The remaining fruit has dropped off. There is sap on one of the branches and I'm wondering if it has bugs or is it just is taking a year off?

Plum fruit turning yellow due to lack of fertilization (talking flower sex, not fertilizers). Other fruits, green, set. The yellow
ones drop from the tree during "June drop" which actually occurs in April here. Yes, I know the question is about apricots but
I do not have any apricot pictures like this.

A. Some fruit trees do take a year off. This is called alternate bearing. However, alternate bearing decreases fruit production by reducing the number of flowers, not the dropping the fruit. Unless the tree is dying I doubt it is due to sap and the bugs.

See the "yellow" plum getting ready to drop? It will abort. The green ones
will continue to develop.

Flowering, followed by the dropping of small fruit, usually indicates poor pollination. Small fruit drops because the pollen was not transferred to the female part of the flower. Or, if it was transferred, it did not result in fertilization.

When fertilization doesn’t occur, fruit may still form, grow a little bit in size, but then yellow and abort or drop from the tree. Fruit abortion typically happens when the fruit gets about the size of a dime or even smaller.

Healthy fruit may abort if the soil is too dry. When soil dries, fruit trees will try saving themselves by first dropping fruit and, if the threat persists, dropping leaves as well.

If weed killers are sprayed close to a tree and the spray (even fumes from the spray on a hot or windy day) may drift toward the tree and cause fruit drop.

Applying too much fertilizer close to the tree trunk can also cause fruit drop.

There are a couple of older apricot varieties that need pollinators. If it is one of these varieties and a neighbor's tree died that was pollinating it then this might also be a problem.

Inspect your tree for insects. Some insects, such as the leaf footed plant bug, can cause fruit drop. If your tree had a large number of these insects feeding on small fruit, it could cause fruit drop. 

Black Spots on Tomato Leaves May Be Septoria

Q. I have these small black spots developing all over my tomato leaves. Any idea what is wrong with my tomato plant? 

Possible Septoria leaf spot disease on new transplants

A. From your pictures it looks like you could have a couple of things going on. The tiny black or brown spots on the leaves may be a disease called Septoria leaf spot. As a precaution, I would apply a fungicide for vegetables immediately and follow the label directions to a tee.

Any general fungicide for vegetables will work. It usually requires several applications in sequence. Push some new growth with a light application of a tomato fertilizer.

Another shot of possible Septoria.

Fungicides are primarily meant for disease prevention, not for curing a disease once the plant has it. Applying a fungicide protects new growth as it emerges so new growth should be healthy while the infected growth does not get worse.

The other option is to pull it out and start over.

Secondly, never apply irrigation water with a sprinkler; use drip irrigation.

If you bought these plants from a local store it probably came with the plant when it was grown in the greenhouse and shipped to the store. This disease is fairly easy to control if a greenhouse is kept clean and the plants kept healthy.

Such is the problem when buying low-priced transplants. They were most likely infected when you bought them. There were probably some leaves already showing these spots.

Your other pictures show leaves of tomato with edges that are scorching. These scorched margins have a yellow inner margin. This is possible salt damage.

Reminds me more of salt damage but ......

Soak the soil with water. Use a soil wetting agent like EZ Wet or comparable and apply it to the soil to remove salts. Hopefully you amended your soil with compost at the time of planting and you used a pre plant fertilizer.

Also some leaves showed signs of yellowing which may be due to lack of fertilizer applied at the time of planting. Once tomatoes start setting fruit it is important to feed them lightly to continue healthy growth.

Take a look at these fact sheets and pics.

Cornell's Fact Sheet on Septoria on Tomato

Missouri Botanical Garden Fact Sheet on Septoria on Tomato

Deformed Lilac Leaves Maybe a Sign of Problems

Q. My lilac bush had some leaves on it that suddenly look like they are deformed. What is the problem?

A. Deformed or crinkled leaves can indicate several things. If the edges of the leaves were damaged, scorched, the interior of the leaf will continue to grow while the dead margin will not. This can cause leaf deformity called cupping.

Stink bug

Feeding damage by some bugs on leaf buds before they open can cause crinkled or deformed leaves. These include the stink bug group of insects such as the leaf footed plant bugs. Look for bugs on the
bottom of the leaves or crawling on stems.

Leaf deformity can be caused by “weed killer” sprays that drifted on the foliage during windy or hot weather. Some herbicides, like dandelion killers for lawns, cause leaf deformity if it comes in contact with leaves as they are enlarging or expanding.

Squash bugs, one of the stink bug types

Bottom line, most likely the damage is temporary and as more leaves develop they should be normal. However, if you inspect the plant and see these types of insects apply an insecticide for ornamental plants and spray leaves and stems during early morning hours. Spray the undersides of leaves because this is where most the bugs hang out.

Make sure the plant gets enough water. This is a plant that likes compost and wood mulch, not rock mulch. Lilacs do not like rocks covering the surface of the soil. Every year apply 1/2 cubic foot of compost on top of the mulch and water it in. Use a high phosphorus fertilizer that promotes flowering of woody plants.

Mildew on Roses Have Common Link

Q. My roses are covered with mildew.  I have sprayed them and hope they will recover.  I have not had this problem in years.  What causes mildew and how do you keep it from coming back?

Powdery mildew of roses, severe

A. Diseases develop on plants when the environment is just right for that disease, disease organisms come in contact with the plant and the plant must be susceptible to it.

Let’s break each of these factors down. Remember, when dealing with diseases it is most important to prevent diseases from happening rather than cure them with a pesticide after the fact.

Powdery mildew of roses, or powdery mildew of any plant for that matter, develops best in shady spots during cooler times of the year and when it is moist. It does not like to develop in full sun and when it is hot and dry.

We see powdery mildew during cool weather of spring and fall and times just after it rains. It is common when roses are grown in shady spots and watered with sprinklers.

Powdery mildew of weeds

Powdery mildew can be spread by splashing water. This can be from rain or sprinklers. It can also be spread by hands, pruning shears and wind.

Powdery mildew likes some roses better than others. The variety of rose and how healthy it is has a lot to do with how often you will see powdery mildew on it.

So if you want powdery mildew on roses then grow a variety susceptible to powdery mildew, don’t fertilize it very often, prune it incorrectly, place it in the shade and water it with sprinklers.

The flip side is best for disease free roses: select a variety resistant to powdery mildew, plant it in at least 6 to 8 hours of full sun each day, apply compost and wood mulch to the soil, keep it healthy with at least one application of a rose fertilizer every year and irrigate using drip irrigation.

These links may help you with some general information on powdery mildew.

http://xtremehorticulture.blogspot.com/2014/12/euonymus-plants-have-white-spots-and.html

http://xtremehorticulture.blogspot.com/2015/01/pick-right-variety-of-roses-for-desert.html

Hugelkulter Mound in the Desert?

Q. I have been reading about building a Hugelkulter mound. My husband and I are in our 60's and the less we have to be on our knees the better it is for our backs. I wonder if we could build a Hugelkulter mound out of desert materials? Every article I've read seems to be in a forested area where wood is readily available.

A. I have to be honest with you. I have never heard of this before so I had to do some digging (not literally) into the subject. I also have to admit I don't know anything about it but I did find someone to refer you to. I met her a couple of weeks ago at a class I was teaching in Arizona.

Hugelkulter on Wikipedia

She is a permaculture advocate and a delightful person. I have not visited her place in Arizona but she is enthusiastic and someone I would recommend you contact for more information.

Christine Baker

928-564-2642

christine@highdesertpermaculture.org

www.highdesertpermaculture.org

Perhaps there are others out there who can chime in. Let's all remember this IS the Mojave Desert.

Consider Banks Rose in Desert Landscapes

Bank's rose is not a repeat bloomer so it only blooms once in the spring. The rest of the year it is green.

Yellow Banks Rose

Trellised for a western exposure and filtering light on a hot summer entry. Spring.

Fuzz Balls on Oak Leaves Damage

Q. I found these fuzzy things on my oak leaves. What are they and should I be concerned?

Oak leaf gall caused by  tiny wasp

A. These fall under the general category of plant galls. Galls are swellings of plant tissue and located on the roots, stems, trunk, leaves and flowers. Galls can be caused by insects, diseases, nematodes or mites.

This particular gall is on the leaf of oak, and my guess it is ‘Heritage’ live oak. These leaf galls are very common to oak and caused by a tiny wasp. The purpose of the gall is to protect the developing youngster until it is mature and exits the gall to find a mate.

Later on in the season you will see a small exit hole and the gall will probably turn brown or the leaf may turn brown and drop from the tree if the infestation is quite severe.

Ash flower gall caused by eriophyid mites feeding on flower buds

The basic lifecycle is for the female to lay an egg inside the leaf or on a leaf surface. The egg hatches and the very tiny larva eats the plant tissue inside the leaf. It also releases chemicals that control the growth of the leaf around the area where it is feeding.

This disturbed area grows in response to the feeding and causes the leaf to grow into a tumor-like growth totally surrounding the youngster. Inside this gall the youngster can continue to feed protected from predators and the environment.

Eventually the youngster grows up into an adult and exits the gall in pursuit of a mate. Once the mate is found, the life cycle repeats itself. In some cases a large number of these wasps can exit numerous galls and build a large population that can cause leaf drop.

These leaf galls normally don’t present a problem and I would just ignore them. However if they do create a problem you might consider applying a tree systemic insecticide to the soil surrounding the tree near the source of irrigation water. I would apply it as soon as you see leaf galls developing in the spring.

A picture of this same oak gall appears at this website by Armstrong with a short description along with a bunch of other galls. http://waynesword.palomar.edu/pljuly99.htm#insects

You can learn more about plant galls by visiting this website located at Brandeis University.

http://www.bio.brandeis.edu/fieldbio/Plant_Galls/samplepage.html

Leaf drop could also occur from excessive shade and a lack of water or applying water too often. You should not be watering daily. All it takes is one or two missed irrigations and you could have leaf drop from a lack of water during hot, dry weather.

Watering too often would cause root rots and leaf drop and a sudden death of the tree during hot weather.

Applying a heavy dose of nitrogen fertilizer close to the trunk could also cause leaf drop and possible tree damage.

No Water? No Vine.

Q. Is there any decorative vine which will prosper in Southern Nevada with no irrigation at all except what nature provides? The situation is the bare-looking north side of a wall where I do not want to extend irrigation piping.

A. There is no vine that will make it here without additional irrigation. We average 4 inches of water each year. I have seen it without rain here for over one year. That irrigation might come from a neighbor but it will not survive without some source of water.

We do have wild grape and some other vines that do grow along waterways coming from mountain runoff but they have water and grape roots can grow to depths of 30 or more feet.

The key to avoiding a lack of water is to either store the water in modified plant parts like cactus or have very deep roots that can tap into a water supply that we cannot see.

Microclimates Have Profound Effects on Gardens

Q. I live in North Las Vegas and am considering a vegetable garden in my backyard when I retire in January of ’16.  I have adequate space on east or west side of the house.  However, the west side has a high wall that blocks off the afternoon sun. Which side would be best for the garden?

Shade can have a dramatic effect on the temperature/humidity/light
microclimate of a yard.

A. I think of growing areas in the yard in terms of microclimates. It sounds like you may have two different microclimates going on; the warmer but shadier west side and the cooler east side.

I would consider having growing beds on both sides if they are significantly different in their environments. These two different microclimates can extend your production by a couple of weeks or more in the spring and fall; earlier spring and later fall production in the hotter microclimate and later spring and earlier fall production in the cooler one.

Reflected light also counts as light that the benefits plants as long as it is bright enough. I would not discount the west area simply because you have a wall on the west side. I would consider painting these walls to reflect more light or cover their surfaces for the same reason.

Think back when you have been in both of those areas and your impressions regarding their different microclimates. Was one microclimate quite a bit different in seasonal temperatures than the other? If these microclimates are so similar you do not get any advantage then I would put it on the east side. 

Barrel Cactus Problems Tied to Water

Q. Over the years I planted perhaps 10 different golden barrel cacti. Nearly all died the same way. I first notice a hole in the main body of the plant. It looks like a rodent gnawed the hole. I have never found anything inside the plant. The plant retains its color and appears healthy. After about a year the root system is gone and I remove the plant. Can you explain?

Golden barrel cactus with pups

A. When I lose a barrel cactus that way and the hole is at the bottom of the plant it is usually from poor soil drainage and watering too often. The roots rot as well as the interior. Reduce the frequency of your watering and make sure the soil drains extremely well.

            If you catch the problem early enough you can arrest the damage by shutting off the water until the plant recovers. After that, water less often.

If they are watered more than once every two weeks this might be the problem. They rely on storage water during times of water shortages. The size of the plant increases after a heavy rain and decreases when water is scarce because of the stored water.

The only creature that I would think might be interested in barrel cactus and might be able to damage them are ground squirrels. But they usually harvest fruits from them, not the fleshy interior.

Viragrow Delivers! : Options for Fertilizing Vegetables; Organic vs Con...

Viragrow Delivers! : Options for Fertilizing Vegetables; Organic vs Con...: Viragrow's Kelp Meal Q.  I was reading an article from Linn Mills about foliar fertilization,Linn was saying to spray tomato plants...

Viragrow Delivers! : Vegetables, Sprouts and Herbs for Las Vegas and Wh...

Viragrow Delivers! : Vegetables, Sprouts and Herbs for Las Vegas and Wh...: Do you have some extra seed? Ever consider growing sprouts with them instead of letting them go to waste? The plant parts we eat helps us...

Argentine Cactus is Yellowing

Q. I have two quite large Argentine Giant cactus, each with many pups they've offset from their base. They are both located on a West facing patio, one is in a large pot and the other is planted in native soil. The one in the pot always turns yellow on its south side this time each year. The one in the ground does not. The potted one has been in that pot for about seven years, and I generally give it fertilizer a couple times a year.  I think I've even tried a bit of iron, though I don't really think that is the problem.

A. The usual reason for this cactus becoming a yellowish in color is sun damage, particularly if it only on the side facing the sun. Other possibilities could be the buildup of salts in the soil, lack of nutrients, root damage and cold damage. But the bottom line is stress.

Because the cactus has a restricted root system and has no ability to take water from deeper or surrounding soils, the plant may be more stressed in a container than the one planted in the ground. That's how I would view it.

The yellowing is resulting from stress. I think the plant in the container will stress more easily than the one in the ground. This cactus will turn yellow (side facing the sun) in a stressful microclimate when planted in the ground.

You should consider all of these as possibilities but I think it is most likely sun damage or bleaching of the plant tissue by intense sunlight. They will do a little bit better without so much intense sunlight, particularly the one in the container.

All that being said, make sure that the soil has adequate drainage and you are not watering too often so that you can eliminate root damage because of the soil kept too wet.

Choose a good fertilizer for it. I like Cactus Juice as a fertilizer for cacti and succulents. I've had a lot of good reports from people using this fertilizer on them.

When you water it next time make sure you add enough water so that a good 20% of the water applied comes out the bottom holes or moves past the roots to keep the salts flushed.

Cactus Baby Separation From Mother is Easy

Q. Is there any way to separate the babies from the mother cactus when they are joined along the stem or do you just let them grow?

A. Yes, you can separate the baby cacti, or the pups, from the mother cactus even if they are growing along its trunk. However, I would let them grow. They are quite interesting in a landscape when they are allowed to grow more naturally.

            The easiest cacti and succulents to separate are those which produce what we call “offsets” or sometimes we call them “pups”. Offsets are pups that are produced separately from the mother plant, usually on short rhizomes. The rhizome is cut which separates the pup from the mother cactus. The pup then is totally on its own and will send down its own roots and establish itself.

            Pups are any “baby cactus” or succulent whether it is an offset or attached directly at the stem. When pups are attached directly to the stem they can be separated from the mother plant with a sharp, sterilized knife.

The pup is allowed to “heal”for several days in a warm environment without any direct sunlight. This healing produces callus tissue which protects both plants from dehydration and diseases.

Once the healing has finished, the pup is placed on top of soil with extremely good drainage where it can root. The soil is moistened about every three weeks during this time. No rooting hormone is necessary.

This may not be the same cactus, but you can get an idea of what it might do.

http://www.delange.org/CactusArgentineGiant/CactusArgentineGiant.htm

it can add a very interesting element to your landscape if left alone.

Pecan Black Bitter Nut Damage Due to Leaf Footed Plant Bug?

Q. I have several pecan tree and some of the nuts I cracked this year have black spots on the nut and others have a soft brown film on part of the back of the nuts. What caused these problems and what can I do to prevent it.? The pecans have been producing for 30 years and  I have never had the problem until last year.

A. I am guessing that these black spots are on the meat or seed that you normally eat. I am also guessing that when you eat this pecan meat that it is bitter. If you are moving your head up and down in agreement then this is insect feeding damage by one of the stink bugs.

Visit this page to see black spots on the meat

We do have stink bugs in Las Vegas but one particular type of stink bug or a close relative is the leaf footed plant bug which also damages pomegranates, pistachios and almonds.

Closeup of leaffooted plant bug. Photo contributed by Bill Stillman.

This feeding damage can cause the entire nut to drop off the tree or can cause these black spots to appear on the meat. To eliminate this kind of damage you would have to spray the entire tree with an appropriate insecticide.

You would have to start early because they will begin building their population on the tree as early as April. These insects also feed on tree leaves, vegetables and all of our major fruit trees. They overwinter on ornamental plants that remain evergreen in our landscapes.

The adults have wings so they can fly from neighbor to neighbor. Soap and water sprays will kill these insects if they are sprayed directly with this concoction. Soap and water sprays have no residual so no poison remains when it dries. This can be an advantage and disadvantage.

Other sprays are fruit and nut sprays that contain synthetic pyrethrins or pyrethroids. These will also work but the main problem you will have is getting the spray to cover the large tree from head to toe. These black spots can be broken off of the nuts and the nuts can be eaten with no problem.

Why Carolina Cherry Laurel Struggles in the Desert

Picture sent by reader of  the Carolina Cherry Laurel

Q. One of my Carolina cherry trees has some branches with brown leaves and the branches were easily broken off.  I have attached a picture of one of the branches.  There is an area of the main trunk, about halfway up the tree, which is very black.

A. I receive a number of questions regarding damage to Carolina cherry or that they don't look very good. The majority of the reasons why this plant struggles here is because it is native to the southeastern United States where the soils are rich and moist. They will struggle here if they do not receive TLC. The other problem may be where they are planted.

Closeup of the trunk. This is usually due to sunburn on the
trunk due to planting in very hot locations in the yard and
leaf loss that allows direct sunlight to damage the trunk.

Leaf drop of Carolina Cherry Laurel. In this case the cement
and bricks surrounding the plant could poise some problems.

            Your Carolina cherry laurel most likely has been damaged by the intense sunlight of our desert Southwest. When damaged by strong sunlight, we see limb and branch dieback accompanied by leaf drop.

Often times this damage is black with brittle limbs and bark that peels. Frequently the tops of these trees will die as well. They tend to look very

sparse in our climate and soils.

            Because this plant is not a southwestern US native, we have to be careful with it here. When planting it, the soil must be enriched with compost at the time of planting and the surface of the soil should be covered with wood mulch, not rock mulch.

            They struggle in very hot locations. This includes the south and west exposures of the landscape particularly close to the very hot walls. They perform better if clustered with other plants with similar soil and water requirements.

Same CCL as above but showing one is performing better than the other when
growing under similar circumstances. It is possible the one on the left will
do the same thing over time. It is also possible there could be some root disease
problems due to the cement and possible overwatering and/or collar rot disease.

            They may develop yellow leaves which would be corrected by applying an appropriate iron fertilizer. The one I always recommend is the iron chelate EDDHA. It is stable when applied to the soil regardless of the alkalinity. This is not true of other iron fertilizers.

Growing Tropical Hibiscus in the Desert is Not Easy

Tropical hibiscus growing in Las Vegas Nevada in the Mojave Desert.

Q. I'm forwarding pictures of my existing hibiscus that turned brown this past winter.  It actually looks like there's some growth on two of them but the others look pretty grim.  Should I give them a chance to grow or start again?  Also, if I do attempt to let these live should I trim them to the ground?

A. It looks like your hibiscus really got hammered this past winter. And this winter was not really that cold. These are most likely tropical hibiscus.

Hibiscus is a common name for a number of different plants with different attributes. These range from the tropical hibiscus to plants that we call hibiscus but are winter hardy in our climate.

Roselle hibiscus growing on MoCa Farm in the Philippines.

Your hibiscus was probably one of the tropical or subtropical types. Judging from your picture, the soil looks like it was hardly improved at all and rocks are strewn along the surface. These issues must be addressed if you expect these plants to do well at all in the future.

They need a lot of soil amendment added at the time of planting. Even though they can handle a lot of heat, they cannot handle the extreme heat and low humidity of unshaded south and western microclimates of the Mojave Desert.

They will look best protected from late afternoon sun and the soil covered with organic mulch. They will also do better if surrounded with plants that need moist, organic soils as well.

I would cut them to the ground in the spring, fertilize and water them and see if they will come back. Pull the rock away from them and put down a layer of compost about one inch thick followed by three inches of wood mulch on the surface. Keep the wood mulch away from the stems of the plants by about 12 inches.

In the future you will treat them like herbaceous perennials; let them grow during the warm and hot months and cut them to the ground after they freeze back. Pile mulch around their base that is three to four inches deep. This may be enough to minimize winter cold damage.

Here is an article we (MoCa Farm) wrote for Food Tank on the growing and culinary use of Roselle hibiscus in the Philippines. http://foodtank.com/news/2014/02/a-love-affair-with-roselle 

Vegetables and Herbs Presentation for Arizona Master Gardeners

This is the Presentation I made to the Arizona Master Gardeners in March, 2015, on vegetable and herb growing in the Mojave Desert. I intended it as a beginning primer for newcomers to gardening in the desert.

If there is a problem downloading this document, email me at Extremehort@aol.com and I will send it to you.