Mexican Fan Palm Removal

Q. We have decided to have our Mexican fan palms removed. Do we need to have all the roots removed or just cut the palms down to the ground, especially the one next to the pool?

One of the "fan palms", most likely favoring California fan palm (because it is "fat" at the base) (W. filifera). Palm trees in general, Washingtonia types in particular, interbreed easily and so the genus can easily be genetically mingled. 

A. If your palm trees do not sucker from the base (date palm, Mediterranean fan palm do produce suckers from the base) then as soon as the top is cut off, the palm will die. Both Mexican and California fan palms have one central bud at the top which is the only place where new growth can occur. Once cut and they die, they will slowly decay if left behind.

            The problem you will have when you leave any kind of stump is the palm trees very slow decay rate. Palm debris decay or rot very slowly. Coir is taken from coconut palms and is used in soil mixes to build soil structure because it resists decay. It is slow to decay and is the main reason I discourage its use in compost piles or use in woodchip mulch. It makes a great semi-permanent component in soil mixes. In both cases you want fertilizer or compost added to circumvent its slow decay. When plants decay, they add to the organic content of the soil and help make it darker.

Remove as much of your palm trunk as possible. The palm roots won’t regrow, but any debris left behind from the trunk will decay very slowly. If you decide to use it in your new soil mix (it is a great addition to soils to improve soil structure), chop it as small as possible and make sure that fertilizer or compost is added to the soil to compensate for the slow breakdown of palm debris.

Remaining Fruit Tree Pruning Classes in January 2022

 

Fruit tree that was pruned to open center

2022

Friday, January 7                9 am        How to Prune and Thin Apple and Pear

Friday, January 14              9 am        How to Prune Pomegranate, Fig and Jujube

Friday, January 21               9 am       How to Prune and Fertilize Wine and Table Grapes

Friday, January 28               9 am       How to Fertilize Fruit Trees (Fertilizer + Iron)

What is covered?

Each type of fruit tree is different when grown in our desert climate. Topics will be discussed for each type of fruit tree and how our climate affects each type of tree.

Selection. Which fruit trees are best for this climate? What tree characteristics should I look for at the nursery?

Planting: Which trees are most wind resistant? How big is the hole? Compost vs soil amendment. How deep should I plant it? Is staking really necessary? How to protect the tree from rabbits?

Growing: How do I know if the tree needs fertilizer? How much fertilizer should I give it? When to fertilize? What fertilizer should I use? Will it grow in rock mulch? Does my tree need iron?

Water: How often to water in the beginning? How much water does my fruit tree need?

Insects: How to control insects that damage the tree? Which insects are the most damaging?

Disease: Which diseases are possible and how to prevent them.

Is Hopseed Bush Poisonous?

Q I’ve seen mixed comments regarding purple hopseed bushes being toxic to animals. Do you happen to know if they are or not? Any help would be appreciated!

A. Keep in mind that about 60 to 70% of all landscape plants are poisonous in one way or another. Toxicity depends on the dose given. I have never considered hopseed a poisonous plant. I checked with another source of information that I consider reliable, and he does not recognize it as poisonous which agrees with my original assessment.

Because this source does not consider this plant toxic and the fact that it was previously used by indigenous peoples as a health remedy, I don’t consider it a “poisonous” landscape plant if eaten in moderation. Not as toxic as oleander, tree tobacco, or yellow oleander for instance which have been grown here by backyard gardeners.

Borers in Pine Trees

Q. I am losing portions of my pine trees at my home. All ten were planted from “live” Christmas trees we bought in the past either Mondale or Aleppo type. Out of the 10 trees, 3 are starting to show complete limbs that are dying. I trimmed some “dead” out of one tree this week and saw numerous small holes on it, so I hit it on the cement and this “worm-type bug” fell out. What is this creature and how did it arrive? Is it causing the damage I see in my trees? And finally, how do I get rid of them before they kill all my pines?  

Flatheaded borer found in pine trees

A. Pines are not a preferred tree of flatheaded borers, like the picture you sent. Flatheaded borers are a problem in many plants but usually not pines. Most of the time in heavy sap producers, like plum and apricot trees, the sap floods an area damaged by insects and “suffocates” invaders like these flatheaded borers. I am not sure if it’s an old tale or not, but I understand that sap that oozes from the damaged branches is first cloudy because of insect feeding, and then becomes translucent as the invader or borer is overwhelmed by the sap and dies.

Stress the Usual Culprit

My guess is that these trees had limbs stressed because of a drought problem and these stressed limbs attracted borers to these living, but stressed, branches. So first make sure that water is being delivered to an area equal to about half the area under their canopy. Next, when water is applied be sure it reaches a soil depth of about three feet to satisfy any drought condition they might be experiencing.

Remember pine trees, just like fig trees and palms, like to have their “tootsies” in water. The trees don’t have to be growing in it, but they like to access it during the hot season, even if the water is deep. They don’t like to be surrounded by a “dry” desert soil.

I don’t think “borers” are totally responsible for branch death, but finished them off when the trees became stressed.

What to do? 

Make sure at least half the area under the tree is getting watered. Plant other deep-rooted plants under the tree to deliver water to a wider area and to make sure. Make sure applications of water are to at least three feet deep. Use a four-foot-long piece of rebar after an irrigation is finished to judge how deep the water "wets" the soil. 

If increasing the water doesn't help, apply a soil drench of borer control insecticides to kill existing borers in the branches. Apply it in May after the tree finishes “flowering”.

Any soil drench containing imidacloprid in the active ingredients and for ornamental trees and shrubs will work and should be applied after the plant finishes flowering.

How to Reduce Water Use in a Condominium HOA; Part 1.

I will go to an HOA Condominium Board meeting to talk about how this HOA can reduce its residential water use. I offered my service for free. If they take notes or visit this blog, it will guide them through this nightmare. I have no idea how many parts this topic will have, “How to reduce water use in a condominium HOA”.

HOA Water Bill

This HOA is concerned about their water bill. In most cases their landscape water use in Las Vegas is about 70% of their total water use. The remainder represents interior use. Some condominiums or townhomes within an HOA have their domestic water use metered and some do not. I would guess (without talking to them) landscape water use represents the highest cost for the HOA on its monthly bills. One thing we know for sure, the cost of water ain’t goin’ down. I believe Samuel Clemens (Mark Twain) once remarked, “Whiskey is for drinking and water is for fighting.” 

First, estimate how much water you are using. Yes, it is an estimate.

1. Gather your water bills for the past 12 months and plot this water use, month by month, for the entire year. This represents your total water use (in-house and landscape) and not your landscape water use alone.

Your total water use should follow a "bell-shaped" curve with the lowest amounts used during the winter and the highest during the summer.

Annual plant water use curve for Las Vegas for averaged three years. Your total water use should follow the same pattern. Notice the bars follow a "bell-shape" from lowest water use values (months 1 and 12) during mid-winter to its highest water use values (months 6 and 7) during mid-summer.

Separate out interior water use from landscape water use. Landscape water use represents about 70% of total water use. Younger families typical use more interior water than older families.

Measure your irrigated landscaped areas:

2. Measure the square footage of the landscape you are watering. It does not have to be exact but the more exact your measurements, the more exact is your estimate.

Actual measurements can be done (most accurate) but these measurements can be taken from an "as built" blueprint or site plan of the landscape or from satellite images (Google Maps). But the measurements should be verified with ground measurements. It is very important that ALL the areas represented by the water bill(s) are included and these are verified.

Make sure any landscape plans you use are accurate. Just because it has a scale on it does not mean it is accurate. If a scale is present it must be verified with actual measurements on the ground, called "ground truthing". In some cases it is more accurate to make the landscape measurements with a "wheel" or tape measure. https://whitefishpilot.com/news/2020/apr/22/planned-condos-get-thumbs-up-from-board-9/

Most landscape plans are drawn to a scale of 1:10, which means that 10 feet on the ground equals 1 inch on paper. For example, a 100-foot driveway would be 10 inches on paper. 

Consider any pools to be part of the landscape area. Pool water evaporation is slightly more than the same area covered in grass unless the pool is covered. Water features are tricky. Submeter them if you think it is important to consider.

Determine which what category of landscape water use you are in:

3. Use this conversion for changing gallons into cubic feet of water or vice versa.

     One cubic foot of water = 7.48 gallons

     One gallon of water = 0.1337 cubic foot

Landscaped water use categories

     0 - 2 feet of water covering the irrigated landscaped area (you are doing a great job!)

     3 - 4 feet of water covering the irrigated landscaped area (marginally acceptable)

     5 - 6 feet of water covering the irrigated landscaped area (you can do better!)

Are you satisfied with your landscaped water use category? Want to save water?

If you want to save water, go to Part 2.

What is "Nonfunctional" Grass?

A new measure passed by Nevada state legislators will make the Las Vegas metro area the first region in the U.S. to permanently ban “non-functional” grass — purely ornamental lawns common to office parks, street medians, and housing developments that require irrigation, but provide no recreational or environmental benefits. - Stormwater Report

This narrow strip of living grass or turfgrass, besides being "nonfunctional", is difficult to water, mow and maintain. It has no justification in any irrigated landscape.

What is Nonfunctional Grass?

Sometimes turfgrass is easy to identify as "nonfunctional", eg eye candy, strictly ornamental and visual. it provides no benefit outside of visual appeal. Sometimes grass is considered functional. Golf courses and athletic fields are considered "essential" because they provide a safe place to play or they return tax revenues to the municipality. Sports fields covered in grass (at least the "functional" part) is considered essential since it provides a safe place to play "rough and tumble" sports like American football, soccer, baseball, La Crosse, field hockey and the like. It might argued that "band practice" on a similar grass covered field does not qualify.

Sometimes "wall to wall" grass is hard to justify in the desert. The "functional" grass can be identified and the "nonfunctional" grass removed and replaced with "desert landscaping". This Las Vegas golf course looks much different now than it did when this picture was taken over 20 years ago. What caused the change? Primarily cost or budget. A golf course or athletic field may have both functional and nonfunctional grass in its area of play.

Twenty years ago the cost of watering an 18-hole golf course (small 18 hole is about 120 acres) was about $1 million dollars per year. Elimination of "nonfunctional turfgrass", or lawn grass used only for beautification, was also one of the seven principles of in xeriscape many years ago.

How to keep your lawn in Nevada? Justify it.

How to Keep Queen Palm Looking its Best in the Desert

 Queen palm is not the best choice when growing palms in the desert. Because of their strong and thick petioles the so-called "fan palms" are probably the best choice. But now that you have it, how do you keep it looking its best?

Can You Straighten a Leaning 20 Year Old Saguaro With Just Water?

 The simple answer is no. Most plants dont grow that way. They grow from their growing points or terminal buds.

This palm was blown over during a hurricane in the Philippines and continued growing from its tips but continued to lean.

Determine Spacing of Plants from Structures and Each Other from its Mature Height

 Whether you are spacing plants from each other or from structures the distance is figured from its mature height. Learn how to do this and more on this episode of Desert Horticulture.

Grubs and What to Do About Them

 Grub numbers can be critical in a successful landscape. Learn what this number might be and how to treat for them in this episode of Desert Horticulture.

Is Kurapia a Replacement for Lawns in Las Vegas?

 Kurapia has worked well in covering highway and freeway shoulders, rooftops, public utility areas, commercial properties, and solar farm landscapes. Not much is known about how it performs in a desert climate. Is it ready to replace a lawn? There is a lot of mixed information out there regarding Kurapia and how successful its been in replacing lawn grasses. 

Below are some pictures of it growing in southern Nevada and Valley Sod's email to me regarding their trials with it in Sandy Valley, Nevada.

Kurapia can be mowed to remove the flowers so from a distance it looks more like grass.

It is not a total replacement for functional turfgrass like sports fields. Remember that visual replacement for lawn grasses does not infer tolerance to wear and play. How much “wear” your lawn receives should be considered when replacing it with a groundcover of any type.

Valley Sods picture of Kurapia grown in Southern Nevada.

We at Valley Sod started investigating Kurapia about two years ago and planted an acre of the material at our farm in Sandy Valley.  During this time, we have learned how the plant grows and responds to different temperatures and soil conditions.

The plants were exposed to temperatures as low as 18 F to 116 degrees F at the farm.  The plants did not go dormant (or turn brown) within any of those extremes. In fact, it prefers the heat over the cold and has an active growing season from March till the end of October. It does handle some shade. In full sun it has a very small leaf whereby in shade the leaf is larger. Kurapia can be mowed, occasionally if wished, to remove the flowers to make it appear more like a turfgrass rather than a (flowering) ground cover.

Valley Sod became a licensed grower of Kurapia two years ago.  We foresee Kurapia as a great replacement for natural turf because of its drought tolerance and preference for sub-surface irrigation.

If this kind of turfgrass replacement interests you contact Mike@ValleySod.com

Plants Don't Use Water. People Do.

 This episode of Desert Horticulture insists they do the logical thing to do...accept responsibility for your landscape water use.

When occasional water is wanted for a plant then watering it with a hose instead of a controller is a better idea.

Only Place in Las Vegas with Rich Compost

I have been asked by many. There is only one place I know about in Las Vegas that has nutrient "rich" compost; Viragrow. What I mean by "rich" compost is that it will fertilize your fruit trees and landscape plants for at least two years. By my calculations, one cubic yard of Viragrow Compost has about $150 worth of fertilizer. That's alot! You cont want to plant directly into it or apply it a few inches from your plants or it can damage them....it is that rich! Thats where the soil mixes come in.

Viragrow's "Organic" compost. Previously called Viragrow's "Vegan" compost. Nothing animal or human used to make it. Just sawdust from lumber mills and tree trimmings.

Compost vs Soil Mix. What's the Difference?

Compost is made to mix in soil. Soil Mixes are already mixed! Soil mixes are "Hamburger Helper" of the landscape supply world, if you will. Any of the Viragrow composts should be mixed with a soil by about one bucket for three buckets of soil....about 25% by volume.

Tractor and bucket filling a pickup bed with soil mix. A small small pickup like the one shown can carry up to about one cubic yard of a heavy soil mix. A standard sized pickup will carry safely about 1 1/2 cubic yards of material.

There are four composts sold at Viragrow:

Viragrow Compost (aka, 166) is made by composting municipal solid waste (MSW) and screening this compost fine enough for use as a topdressing for turfgrass and lawns. It contains a small percentage of composted human biosolids found in the MSW.

Viragrow Compost, aka 166, is a rich compost made and screened at the Inland Empire Composting

 Facility in southern California.

"Organic" Compost (aka, Vegan compost) is made from waste from sawmills composted with mineral fertilizers. No animal or human waste is used.

GS Compost is made mostly from yard waste that is finely ground and screened. It could be classified as a "natural" compost but contains no composted biosolids or MSW (municipal solid waste).

Premium Compost is the same as Viragrow Compost (so it contains composted biosolids) but it is not as finely screened as 166. it is screened so the larger pieces of wood are permitted.

Soil Mixes

 Soil Mixes are made by mixing compost with a special type of sand only available from Viragrow...a screened sand. Other places use inexpensive Reject Sand or fill sand in the soil mixes but Viragrow doesn't. It costs more but it produces a better backfill for plants.

Learn When to Fertilize Landscape Plants Like Podocarpus 'Maki'

 

Podocarpus is sometimes called "Yew pine" or "Budha pine". They can get big but the dwarf versions like 'Maki' are dwarf and remain small. Or is it just because the grow so slowly?

Learn when and how to fertilize landscape plants like Podocarpus 'Maki' when growing in the desert.

Damaged Tree at Planting. What to do?

Trees and shrubs can be damaged at planting time. One disease is particularly worrisome. Learn what it is and what you can do about this. All this and more in this episode of Desert Horticulture.

Do You Like Apples? Specifically 'Honeycrisp' Apples?

 I got two questions on the same day from readers who are growing 'Honeycrisp' apple trees. Is this because you like the flavor of the apple? 

Like wine grapes, every variety of fruit has its own "terrior". When we try a fruit tree in a new climate and soil from its original terrior, where we know it did well, we take a risk. We will not know if that risk paid off or not for about five years after its first successful year of production. I learned my lesson on that with 'Flavor Supreme' pluot which excited me at first until I got to know it better. Like wine grapes, every variety of fruit has its own "terrior". which can produce erratically with late spring frosts and its own genetics.

Right now 'Gala' apple has become the number one apple in grocery stores beating out 'Red Delicious' because of its flavor, storage and shipping qualities. Why did 'Red Delicious' apple (btw, an Iowa apple originally) dominate the apple industry for 50 years? Primarily because you could keep it in cold storage for nearly 12 months. It was not because it tasted great. It was the primary apple grown in eastern Washington state for many years. Now we have many different kinds (sports, aka natural mutations) of 'Red Delicious' and 'Gala' apples for different purposes (color, production timing, size, flavor). So why was 'Granny Smith' apple so popular (third largest producer in the US)? Storage. It will store for a long time, like 'Red Delicious'. for a year or longer. It is certainly not because of its flavor. 'Mutsu' apple, a better suited apple variety for the desert, is a green apple that tastes better than "Granny Smith' but will only store for about two or three months. 

'Mutsu' apple ready for harvest. In my opinion 'Mutsu' apple (spur type) is a better choice for desert climates than 'Granny Smith', a tip type apple tree.

'Honeycrisp' apple was developed in the Minnesota market as fresh fruit. It was nearly discarded because it didnt ship or store very well, a necessity for commercial production. 

I dont know how it will perform in a hot desert climate like we  have in the Mojave Desert. I have never tried it. All of the flavor and texture tests came out of Minnesota so we know it does well and tastes good in the upper Midwest. When trying it outside of its normal 'terrior' be prepared to evaluate it for about five years.

Remember the words 'terrior' and 'sport'. Both are important when it comes to backyard production.

What Length Can Drip Tubing Be? How Many Gallons Can it Handle?

Recently I saw quarter inch blank tubing with a length of  over 80 feet! Of course this is too long for quarter inch tubing. But how long is acceptable? How long can drip tubing be extended and still work? How many gallons can a length of drip tubing be designed to handle?

I put this original table together just to answer those questions.

"Half inch" drip tubing with embedded emitters

Approximate Water Capacity for Different-Sized Drip Tubing

Hose Size1 (in)	Hose Size2 (ID) (mm)	OD3 (in)	ID4 (in)	Wall Thickness5 (in)	Max Flow  @ 5 fps6 (gph)	Max Flow    @ 1.5 mps (Lph)	Max Run7 (ft/m)	PSI Loss8 (per 100 ft/30m)
¼ inch	4.3mm	.25	.17	.05 – 1.0	30	120	30/9.1	15.0
½ inch	17mm	.67	.62	.05 -.10	240	960	200/61	9.6
¾ inch	20.8mm	.92	.82	.10	320	1280	480/146.3	5.8
1 inch	26.7mm	1.15	1.05	.10	720	2880	960/292	3.8

¹ Common generic terms for hose sizes; quarter-inch, half-inch, three-quarter inch and one inch. A hose size can have several similar sizes that may be called “half inch”. Always buy name brand drip tubing, blank tubing and fittings for consistency and match their sizes.

² Hose size is not yet standardized. For instance, half inch hose is available in 15, 16 and 17mm internal diameters (ID). The ID will affect the PSI Loss of water pressure inside the tubing and affect its flow rate. Hose size for carrying water is always based on ID (Internal Diameter). Outside diameter (OD) may be used for PE fittings that grasp the outside of the PE tubing such as compression fittings. Sizes you find may not be exact but approximations. Always match your fittings to the ID or OD of the tubing.

³ Outside Diameter (OD) of the PE tubing.

⁴ Internal Diameter (ID) of the PE tubing.

⁵ “Wall Thickness” can vary with different PE tubing. Some PE tubing has thinner walls than others. Different sized drip tubing (e.g., half inch tubing) can affect how much PSI can be used before it fails. Thinner walled tubing is more appropriate for gravity fed systems or lower PSI.

⁶ Five feet per second (5 fps) is the max speed (velocity) water is designed to travel in piping or tubing for pressurized irrigation systems. Velocities greater than this will contribute to “water hammer” , fitting failure, and pipe/tubes bursting.

⁷ “Maximum Run” is the maximum length PE tubing is installed due to a significant loss of water pressure when it is flowing (PSI Loss).

⁸ “PSI Loss” is the loss of water pressure (PSI) because of the friction (rubbing) water has against the inside of tubing. The "PSI Loss" is measured at the end of a distance that the water might flow and typically standardized at 100 feet (30 meters).

USDA Accepting Applications to Help Cover Costs for Organic Certification

 Read the origina.post from USDA here

The U.S. Department of Agriculture (USDA) today announced that organic producers and handlers can now apply for funds to assist with the cost of receiving or maintaining organic certification. Applications for the Organic Certification Cost Share Program (OCCSP) are due Nov. 1, 2021.  

OCCSP provides cost-share assistance to producers and handlers of agricultural products for the costs of obtaining or maintaining organic certification under the USDA’s National Organic Program. Eligible producers include any certified producers or handlers who have paid organic certification fees to a USDA-accredited certifying agent during the 2021 and any subsequent program year. Producers can be reimbursed for expenses made between Oct. 1, 2020 and Sept. 30, 2021 including application fees, inspection costs, fees related to equivalency agreement and arrangement requirements, travel expenses for inspectors, user fees, sales assessments and postage.

This funding will be complemented by an additional $20 million for organic and transitioning producers through the Pandemic Assistance for Producers initiative. More information on that funding will be available in the coming weeks.

Plum Tree has Fireblight? I Don't Think So.

Q. I'm hoping you can help save my plum tree. It has fireblight, I cut off the infected area but it spreading to the rest of the tree. It has these gel filled sacs that are moving through the tree and not sure how to treat it. Can I save the tree?

Early summer growth with fireblight. Happens around May in Las Vegas and is only in Asian Pear, European Pear, Apple and some ornamentals in the rose family of plants.

A. It is not a disease such as fireblight. That disease only attacks European pear, Asian pear, and apple as far as fruit trees go. Not plums. It will damage some ornamentals in the Rose family of plants. Damage from fireblight is seen starting in about May. Your “gel filled sacs” are typical of plum when limbs over half inch in diameter are damaged from anything; diseases, natural causes, or insects. Damage this time of year usually comes from the sun (sunburn) or from boring insects or both.

Sap oozing on plum trunk and limbs can make you think of fireblight, but it can't be.

“Sunburn” damage can be a two-edged sword; it can cause damage on its own, but it can also lead to further damage by boring insects that we refer to as “borers”. Borers in our climate are beetles with an immature form (grub) which tunnels into damaged stems. The kind here are never found in the ground. Frequently these stems may first be damaged by intense sunlight (sunburn). If this damage is caught early enough (March through June) and it is light, any grubs can be easily pruned or cut out with a sanitized hand pruner or knife. If left to do their tunneling until later in the season (June through September) or if the attack is severe, the only treatable option is chemical control using a soil drench of an insecticide. Looks like you are left using a soil drench.

These pockets of sap coming from the trunk and limbs, accompanied by dieback, are positive indicators of borers. By this time of year and when you see dieback, borer damage is in an advanced stage. Find the Bayer insecticide for borers in fruit trees and apply it as a soil drench around the tree following the label directions.

An irrigation moves this poison inside the tree from the roots. This soil drench treatment allows the “poison” to move throughout the entire tree. You cannot eat any fruit from this tree the following year. The parts of the tree that are dead will not come alive but hopefully you will see some new growth from the trunk or limbs after about a month. You will know if you are successful or not by October.

Hand Pruning vs Hedge Pruning

Q. I heard that hand trimming bushes was better than using hedge trimmer.

Hand pruning, or pruning with a loppers or hand pruner deep inside the shrub using three or four cuts.

A. Yes, it is. It is not only “better” but it is faster, needed much less often and with less cleanup involved afterwards. Pruning with a lopper is done once every two years or even less often. Hedge shears used when the plant is grown as a hedge. Pruning with a hedge shears is done twice or sometimes three times a year or more. Pruning with a hedge shears eventually weakens the plant and makes the shrub look ugly in five years. Once done and finally noticed, it is impossible to correct quicky if at all. Most likely the shrubs will need to be replaced rather than pruned.

Pruning with a hedge shears requires three or four pruning trips each year and causes plants to become "leggy" after a few years.

Timing is also important. Pruning with a hedge shears is done ytime of the year by “professionals”. When hand pruning, remove stems after the shrub finishes flowering or in the winter if it flowers in the early spring. Correct hand pruning with a lopper removes two or three large stems from deep inside the plant once every two years. That’s easy to clean up. Hedge shears focuses on removing the new growth at the ends of stems. That cleanup requires a blower.

Euryops Daisy Getting Leggy

Q. My green euryops daisies were doing beautifully last spring and summer, but this year they became tall and leggy and grew poorly. It is late July now. Is that too late to prune them back?

Euryops Daisy in a planter in Las Vegas

A. Euryops daisy grows best at temperatures from 40F to 100F. When it gets above 100F then this plant struggles. The ideal temperature for their growth is probably about 65 to 75F. If on the west or south side of the home, move it to the east side (cooler microclimate) this fall (milder time of year) if possible and put other plants around it that like water. Cut them back hard and improve the soil with organics such as compost when planting. Use a pre-plant fertilizer mixed with the soil like the one for roses or tomatoes. If you use a “rich” compost, then extra fertilizer is not needed. They will not like it much if surrounded by rock.

            As far as cutting them back now, wait until daytime temperatures are 65 to 75F and then prune them an inch or two above the ground and let them regrow from the base. In the Las Vegas climate, that would probably be some time in October. When pruning, cut them back very close to the ground and let them grow back before it gets cold this winter.

Eucalyptus Leaves Used as a Mulch

Q. What’s your opinion about using eucalyptus leaves as mulch?

Eucalyptus microtheca growing in Las Vegas

A. There are reports that leaves from some plants will sometimes inhibit the growth of others. I think this is what you are referring to. This inhibition of growth was first thought to be due to competition for water and plant nutrients, but plant chemicals have been isolated from some fresh plants and found to affect the growth of others. How this works depends on the plant making it and their “allelopathy” is not consistent between different types of plants. All this makes it difficult to isolate and prove its existence. It is clear to me that plants “communicate” in ways we have not thought about but how this happens is not clear.

Read more about eucalyptus leaves as a mulch here

Eucalyptus leaves as a mulch here

The classic example of this is black walnut inhibition of growth (allelopathy) on plants growing under its canopy. Other examples of “allelopathy” exist such as in creosote bush, lavenders, salt cedar, bermudagrass, and others. It is not just a simple answer but varies between allelopathic plants and plant parts. Personally, I have never tried using eucalyptus leaves. I prefer to use wood chips as a mulch or a combination of plant parts from different plants.

Oleander as a composted mulch

One way around this is to compost, or “rot”, eucalyptus leaves. It seems that in most cases the plant or human “toxins” are decomposed as well rendering what’s left as nontoxic to both plants and animals. So, for this reason, I would not use uncomposted leaves of any kind without composting (rotting) them first unless I knew the leaves were not toxic to other plants in the first place.

Kurapia as a Turfgrass Replacement

 Q. Have you ever heard of kurapia as a ground cover? I wonder if it would succeed here in Las Vegas. I know that this recommendation is from a landscaper in California’s Central Valley, so they have a similar climate.

Kurapia is a lawn weed that is marketed as a replacement for a lawn.  Photo from Valley Sod Farms, Sandy Valley, Nevada.

A. I had not heard of it until now. From a marketing perspective it is supposed to be a lawn replacement for grass. It may be a visual lawn replacement but will not withstand traffic or play. Kurapia was started from the native plant, Lippia nodiflora (a synonym for it is Phyla nodiflora for those into its botany), that marketing people say was found in the coastal regions of Japan. But Lippia is native to the tropical and subtropical areas of South America and the United States. This calls into question its tolerance to extreme desert temperatures and low humidity. Growing in our desert soils should not be a problem for it.

Read about Lippia here

Lippia can be a common weed in most of the US. The Central Valley in California is arid but not an intense desert climate like ours so how it will perform during  the cold winter temperatures of Las Vegas is unknown. For example, fruit trees grow great there but you have to be a bit more careful with them in our desert climate. Because it is subtropical, like hybrid bermudagrass, I am guessing it will turn brown when fall and winter temperatures reach into the low 40’s.

Read discussions about Kurapia here

I also read about it at the UC trials in the subtropical and Mediterranean climate of the UC Riverside campus. It is a Lippia, which can be a common weed in some lawns. Ornamentally it is considered a groundcover, so it is not meant to withstand heavy traffic and, at 3 inches tall, it does not need to be mowed. It is primarily a visual lawn replacement during warm and hot months. So, in my opinion it is not a turfgrass replacement where lots of walking or anything heavier is expected. You can also mow it if you want it shorter than 3 inches tall. I suspect it might have difficulty growing in the hot and dry Western and Southern exposures of a landscape.

Read about the UC irrigation trials here trials done in Davis, California

Read about UC recommendations here

It spreads about 3 feet in diameter so, like hybrid bermudagrass, planting it 12 inches apart in a triangular pattern will cause it to cover the area in about 2 months during warm weather if watered regularly and fertilized monthly during establishment.

It will perform best if the soil is amended at the time of planting, and not grown in extremely hot locations. They claim it uses less water than tall fescue lawns, about the same as a bermudagrass lawn. The water use for it has not been established in southern Nevada. It has been established for other locations but ET (water use) varies between locations.

Update: Valley Sod Farms in Sandy Valley, Nevada, contacted me and gave me more information regarding their trials with it there. For more information contact Mike@Valleysod.com