Xtremehorticulture

Tree Aloes From Africa or Madagascar

Q. Do tree aloes survive in Las Vegas especially any of the tree aloes from Africa or Madagascar? A. “All cacti are succulents but not all succulents are cacti.” That is a cactus axiom. In other words, there is more that restricts geographic distribution of cacti than whether they are succulents or not. Succulents have a wider range of habitats than cacti. Many succulents are “arid” in their climate extremes and some cacti are meant only for deserts. Another axiom is that, “All deserts are arid but not all arid areas are deserts.” Just because its from somewhere arid doesn’t mean it will survive in a desert. Even some cacti from South America struggle when planted in the Mojave Desert primarily due to differences in light intensity and temperature extremes. Plant tree aloes on the east side of a landscape near the shade of a building if you want to be safe. Use wood chips as a mulch or plant them with compost. Never plant them in full sun. An example of climate related damage is the damage of desert climates to Spanish bayonet, a smaller “tree aloe” that is arid. Another native yucca to the east coast is Spanish bayonet (depends on who is talking, Yucca aloifolia or Y. gloriosa). It is a woody evergreen shrub also native to the Atlantic and Gulf Coasts of the United States. Unfortunately its common name is also aloe yucca, dagger plant, and Spanish dagger. The Spanish bayonet should have dark green, stiff, dagger-like leaves with sharp tips that can pierce through thick clothing. It can grow up to 15 feet tall, but often flops over from its own weight. The Spanish bayonet should produce large (1-3 feet in length) showy white flowers that droop downward. In the Mojave Desert however it yellows and scorches when planted in full sun and when soil organics are running low. Again, with few exceptions, most tree aloes grow best in warm, dry, arid, climates; warmer than the Mojave Desert but without the high light intensity of direct sunlight. Another thing our desert climate has against tree aloes are our temperatures. Those temperatures may or may not be changing. Scientists are not sure. Some tree aloes can tolerate temperatures below freezing for short time periods. Others can’t. Tree aloes have at least four things going against them in our climate; they need water, they need some soil improvement, they should avoid high light intensities, and avoid the low temperature damage they get during our winters. Temperatures are Changing It’s not tropically wet like Madagascar yet, but if you have had sweet oranges (‘Valencia’, ‘Washington’) that survived our winter temperatures then maybe you are okay at least for a few years of growth. How many? Not sure. During the winter of 1989-1990 we had temperatures as low as 12F at the Painted Desert golf course. Those temperatures would have killed all citrus, including the cold hardiest types. Citrus, like aloe trees, is considered at the least subtropical. Select the most winter cold tolerant types of tree aloes to be sure. Water Water is added with periodic irrigation. How often? Not sure but the taller the plant the deeper and less often water is needed. It depends on the soil and the type of tree. Add more water and irrigate wider as the tree aloes get bigger. Soil Organics Our soil is ultra-low in soil organics. Add between 10 to 20% (normal amounts are 25 -30%) compost to the soil. This means to add one quarter to one half bag of compost when planting and mix it with the existing soil. Compost holds water but it drains the soil. In summary, select the more cold tolerant aloe trees. Plant these on the east side of a landscape in the afternoon shade of a building. Plant them on a hill for drainage, add a small amount of compost to the soil when planting, plant wet and water periodically. Start small when using them and plant fewer in number.

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Newly Planted Landscape Tree Moving in Soil

Q. I have a mesquite that I planted two years ago.  It has grown rapidly, and I continue to move drip lines to the edge of its canopy.  However, it apparently has “bundled” roots – roots that are quite loose when moving the plant from side to side. Are there any possible remedies, or do I just wait and hope the roots spread? A. I usually handle that type of problem when it is planted, not now. Sometimes a plant comes like that from the nursery and sometimes it arises from how it is planted. Plants that I buy with roots not spreading correctly, I return. Those kinds of plants should not be sold. Most nurseries don’t sell plants that “don’t have roots spreading out” (kinked roots) since the mid 1990’s. Nurseries now have a problem with growing some plants too close together and those plants “flopping over” when they are no longer staked. Most nurseries have a return policy. Some plants like that are discounted. Kinked roots often times relate to how many seasons of growth there are in the same container. They are bought with hopes that “bundled” (overgrown) roots will spread into the surrounding soil when planted in the ground in the soil correctly. They won’t. Stop wishing. Overgrown roots will continue to grow in circles and are permanently deformed. Nurseries are pretty good about removing or culling “root deformed plants” (plants not growing well) when they see them. Sometimes, when the roots of these plants are starting to get deformed, the root growth can be “straightened out” with some minor root surgery, spreading out the roots, realignment, etc. This type of root surgery may include some top pruning or heading back but seldom does. Top pruning depends on how much of the roots were removed. Consumers like “big plants”, the bigger the better. The thought is, “Increased money requires big plants”, rather than improved plant health. When I am planting, I always do two things; check the plant for stability after its planted and stake the plant to keep the roots from moving. Checking the plant for stability in the soil is making sure it was planted correctly. Secondly, plants are always staked, even if the stake is made from bamboo and comes with the container when it is bought. Usually it takes after planting (five gallon containers and smaller, depends on the size of the plant) is pushing the stake into the ground further and a small amount of green plastic nursery tape to keep the plant’s roots from moving. Staking keeps the roots stable and growing in the ground during gusting winds. Wind gusts can be unpredictable. That’s why I am constantly harping to “plant in wet soil”. Wet soils are “dirtier”, a “pain in the rear end”, and heavier, but they remove “air pockets”, fill gaps around roots, and stabilize plants in the soil. Plant wet whenever possible even when it is uncomfortable.

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White Grubs Feeding on Roots of Fruit Trees

A “new” insect pest was found in the soil surrounding apricot trees at the privately owned Orchard at Ahern (entrance off of Clarkway Drive, near West Bonanza Road in Las Vegas, Nevada). It was new for fruit trees anyway. Some of you may know about it feeding on soil organics created by adding compost or decaying wood chip mulch to the soil. The insects in this group improve soil health by feeding from organic matter and recycling fallen fruit. Insects that feed on decaying organic matter are called Detritivores and include springtails, termites, ants, dung beetles, ground beetles and others. My feeling is that the young larvae come from a beetle. Those beetles that “eats” compost and gets some energy from it is suspect. Sometimes these “worms” (insect larvae mistaken for legless worms) “mistake” the small feeder roots of plants (living) with dead “organic matter”. Large numbers of these types of larvae feeding in the soil can cause damage to established fruit trees. How to know? Look for exit holes of adults at the base of any fruit trees. Those adults are gone. Adults mean they have “children” or larvae present in the compost or wood chip mulch. Any liquid insecticide will work if it comes in contact with this insect. But it must be in liquid form or made into a liquid to work. Use a soil drench if the label permits. Follow label directions.

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Prickly Pear Cactus also Called Nopal Cactus

Q. I do not remember exactly how old this cactus is, but I think about 20 or so years! This cactus has not had this many flower buds! I will not wait for this plant to flower! Can you identify this cactus? A. That is Opuntia spp. This form of edible cactus (aka nopal cactus, bunny tails, beaver tails) has its origin in the dry parts of central America, mostly from central Mexico, but its distribution extends through the Americas. I grew edible selections of this cactus about 15 to 20 years ago when I gave up due freezing damage because of our Mojave Desert winter freezing winters. Lower parts of the Sonoran Desert are significantly warmer in the winter and hotter during the summer than lower parts of the Mojave Desert. They are also known as Nopal cactus because humans from central Mexico, after removing the spines (technically called glochids), would cut the succulent pads into strips. These “bite sized” strips are known in Spanish as nopalitos and the fruit (from the flowers) are called tunas. Some of the better selections (V1, F1 taken from lower elevations of the interior of Mexico) are quite versatile. These plants provide nopalitos, tunas (fruit naturally colored as red or yellow), and as a cattle supplement (fodder). The reason Opuntia has the spp. added to it is because there are many different varieties. F1 and V1 are the best selections of Opuntia spp. from the Sonoran Desert. The birds would devastate the best tasting fruits. Non-winter freezing parts of the Mojave Desert support Opuntia spp. as well, but research has not been done on nopal cacti from the Sonoran Desert, probably due to cultural differences.

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Thinning ‘Myer’ Lemon Tree

Q. My Meyer lemon tree this year has hundreds of buds and flowers. Many on same branch or twig. Should I remove some of them, so I have fewer but larger lemons? A. No thinning of the flowers. The first thinning is done when fruit is about the size of your thumbnail. The second fruit removal is done about four weeks. Aim for about 30 to 40% fruit removal for mature citrus. In about 4 to 8 weeks, you should know where the leaves will be. That’s important for removing sun burned fruit. Remove misshaped, deformed, damaged, doubles or the smallest fruit during the first wave of thinning. On the second wave remove possible sunburned fruit and leave fruit that is or will be. shaded by some leaves. Fruit sunburning on exposed sides (usually west and south sides) and the tips is common in the desert. There is usually no sunburning on the east and north sides. There is a maximum size (determined by genetics) the fruit will reach but it is possible to maximize size in a higher percentage of fruit. Pinch the fruit between two fingers and gently twist it off. Pay close attention to the bottom of trees as a higher percentage of small fruit is located there. Young trees have fewer leaves to photosynthesize and will be better off in the long-term if they’re allowed to focus on their growth. You can leave a few fruit if you want a taste.

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‘Tiny Tower’ May Be a Smaller Variety of Italian Cypress

Q.  I have a space that has a height limit of 10-12 feet.  I want to plant some columnar trees that won’t grow too tall.  I realize that Italian cypress would work but would have to be trimmed to limit their height. Are there others that might work in our Las Vegas climate? For example: ‘Emerald Green’ Arborvitae, ‘Sky Pencil’ Holly, and any others? A.  To get a truly evergreen hedge in this climate is tough. We may have winter cold that kills the leaves of many smaller trees followed by leaf drop. ‘Tiny Tower’, (aka, ‘Monshel’ and ‘Compacta’) from Monrovia Nursery (a production nursery) claims to be only 10 feet tall and 2 feet wide and very slow growing. With age Monrovia claims it will grow 25 to 30 feet tall and 3 feet wide. Others do confirm 20 to 25 feet at “maturity”. What “maturity” means, as far as age of the plant, was not made clear. I would guess that it grows at one foot per year if not watered more often and given fertilizer. Watch out for the flopping of new growth. That tells you are watering too often. Monrovia said it was taken as a dwarf “sport” from an existing Italian cypress. Las Vegas USDA zone classification is 8A through 9B, so it is well within those hardiness zones.

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Benefits of Wood Chip Mulch for Gardens

Q. I have been hearing about the benefits of wood mulch for my garden. What type of wood should I look for and where would I find it?  Do I work it into the soil like my lawn cuttings or just spread it on the surface? A. Three things are important; soil temperature, watering so the soil stays moist, and the size of wood chips. The smaller the wood chips, the faster they rot or decompose. Temperatures warmer than 55F speed up how fast these particles “rot”. Dryness slows down how fast the wood chips rot. The wood chips need it warm, moist and should be small to decompose quickly. For instance, sawdust rots too fast but wood chips too large may rot too slowly. About 1/4 inch to 1/2 inch is perfect. The source of the wood chips is also important. Please don’t confuse “bark” and “wood”. Never use bark for wood chips unless you want it to look pretty and float or blow away. A mixture of wood and bark is okay but not straight bark. Bark chips are mostly decorative. Wood chips are not decorative (pretty) at all. I would call wood chips “rustic” if I were selling it. Bark mulch “looks” are the main reason its bought. When wood chips are on the soil surface it is called mulch. Wood chips used as mulch are not pretty. It’s functional. It’s okay if wood chip mulch is larger. In fact, you want wood chip mulch to be large. When small wood chips are mixed with moist soil, they are no longer seen. They slowly, over time, become the “organics” part of the soil or organic matter. The rate of decomposition depends on the size of the wood chips, how regularly moist the soil becomes, and soil temperature. Lawn clippings are “green” (not “brown” like woodchips) when first mowed. Grass clippings rot quickly compared to wood chips. Wood chips have a carbon to nitrogen ratio of around 300 or 400 to one (300 or 400 carbons to one nitrogen). There is a lot more carbon present compared to nitrogen. To get wood chips to release their nutrients locked up, you must add some nitrogen fertilizer. Lawn clippings have a carbon to nitrogen ratio of about 40 or 60 to 1. There is a lot more nitrogen fertilizer in green grass clippings than in wood chips. “Green” mulch doesn’t need extra fertilizer. “Brown” mulch does. What does that mean to you? As wood chips rot or decompose you must add nitrogen fertilizer to it. Grass clippings don’t need any added nitrogen. Grass clippings act like a complete fertilizer when it rots or decomposes. It is the complete package. Use finely ground wood chips when mixed in the soil and add some nitrogen fertilizer with it. Use small chunky wood chips (1/2 inch and smaller) when mixed in the soil.

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Depth of Watering

Q. Many of your articles talk about the depth of the water when watering. Having the drips on top of the ground can make it hard to get the water to the desired depth.  If you want watering at 12″, what is your opinion of putting a piece of plastic pipe to that depth, then just put the drip line down the pipe so it drips at 12″!  If you are worried about spreading the water out, you could always put a larger pipe or plastic junction box at the bottom. A. It does not change how much water it needs. The surface 3 to 4 inches of surface mulch nearly eliminates evaporation from the soil (the E part of ET). I would not use any devices that divert water deeper. It just costs money and adds to the watering confusion. It will need the same amount regardless. Most plants rely on water that fills the soil from “top to bottom”. The depth of applied water depends on the height of the tree. Generally speaking, small trees (less than 20 feet in height) require less water than large trees (more than 40 feet tall).             Did you ever hear of the 40-30-20-10 rule in a landscape? Landscape plant roots range from about 12 inches to three feet deep. The taller the plant, the deeper its roots. Divide landscape plant roots into four equal parts (quartiles). The quartile closest to the soil surface uses about 40% of the applied water, the next quartile uses about 30%, the next uses about 20% and the last quartile uses about 10% of the applied water.             Quartiles are human inventions. As water in this 40% quartile becomes more difficult to extract, the plant uses the next quartile, and the next, and finally the last. Plants don’t use any more “effort” than they need to! For nondesert plants we schedule a new irrigation when this water is about 50 to 60% gone.             So you see, all landscape plants require water to fill the soil so that all their roots are wet from “top to bottom”. Just remember, the taller the plant the more water is applied!

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‘Red Baron’ Peach Flower Color

Q. After watching the beautiful flower color of ‘Red Baron’ peach on your YouTube channel, I want one. Where can I get it? I tried to find it locally but couldn’t find it. A. Try online. I found it at Groworganic.com. It is a yellow fleshed variety that flowers in early or mid March and produces fruit somewhere around mid-July to August. They will ship the tree to the Las Vegas location without soil in late January or early February, but is very difficult to find locally. Plant it (wet) as soon as you get it. Planting it wet should give you about one week of its water needs when planting at that time of year. Purchasing it can be done on this website: https://www.groworganic.com/ I would give the fruit from that tree a high three or possibly four out of five stars. Out of 25 to 30 varieties of peach trees, only three peach varieties consistently received a five out of five stars. The fruit was very good but did not receive a five-star rating. It is a good reliable peach tree for our area. There are many peach trees to select from that produce fruit in our area. Others include the white fleshed ‘Babcock’, ‘Arctic Supreme’, ‘Galaxy Donut’ and ‘Indian Free’ among others. More traditional yellow-fruited types (and taste) include ‘Eva’s Pride’, ‘July Elberta’, ‘Belle of Georgia’, ‘Kaweah’, ‘O’Henry’, and other varieties. Select those that flower after the second week of February to mid March and produce their fruit before mid-August. For backyards and in the desert, always buy them on dwarfing rootstocks. Avoid genetic dwarf trees. Buy them 3/4 inch or smaller, the smaller the better. If they don’t have future limbs at your knees or lower, prune them to knee height after planting to encourage lower limb growth.

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Young ‘Fantasia’ Nectarine Diseased?

Q. My ‘Fantasia’ nectarine survived over the winter. It got leaves and blossomed. Now the leaves aren’t looking great, and the branches are developing black tips almost like they’ve been burned. Is that likely to be black fungus? If I need to dig out the tree and replace it, when would the best time be to do that? Are we too close to summer to try that now? A. This was a rough time for plants this winter. All through the winter this tree should not receive a deep watering more often than once a week. Some time in February is the time to give mesic (water loving) trees (all fruit trees are mesic) a solid watering of watering once a week. How much depends on its size but make sure the roots get water 18 to 24 inches deep. All plants pretty much follow a 40-30-20-10 rule with their roots. First make sure the fruit tree was planted correctly (planting hole dug or the soil at least loosened! three times the container width) and the hole backfilled with an amended soil. Make sure the tree was staked and watered in, the soil around the tree covered with a mulch of some sort. Next, we can address your tree issues. With this very low desert humidity, any leaf of stem disease will not last long. If the tree looks good other than the leaves, let it go. Let the warm, and eventually hot, weather do its job. The leaves look a little yellow so make sure it was fertilized properly in about four weeks if needed. Make sure there isn’t a borer problem present. Nectarines are “glorified peaches”. They can be a problem in peaches and nectarines. By the way, ‘Fantasia’ nectarine fruit got pretty low marks from me at the University orchard regarding tasting the fruit. Not the tree, it did well, but the taste of the fruit.

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