April 2018 – Page 4 – Xtremehorticulture

Difference Between Dwarf and Miniature Fruit Trees

Q. When shopping for fruit trees, I noticed both dwarf and miniature trees available which confused me. What is the difference between a dwarf and a miniature variety? Bonanza peach is considered a miniature or genetic dwarf peach. Commercial orchard is thought that miniature peaches were going to revolutionize commercial peach growing. Unfortunately, the fruit is seldom is good as the fruit produced by traditional peach trees. A. The difference between the two is a difference in genetics (miniature) versus how the tree was propagated or grafted (dwarf). Miniature fruit trees are regarded as genetically different or independent from other varieties. The terms “miniature” and “dwarf” are sometimes used interchangeably in the nursery trade for marketing purposes. This causes a lot of confusion for the consumer. But they are different from each other. Miniature fruit trees (sometimes called genetic dwarf in the nursery trade) are not manipulated to be smaller. Their “smallness” is in their genetics. They were “born” that way. Miniature fruit trees do not have to be grafted to make them smaller but sometimes they are grafted for other reasons. Examples of genetic dwarf apple trees are the varieties ‘Apple Babe’ and ‘Garden Delicious’. Genetic dwarf peaches include Bonanza and El Dorado. Grafted fruit trees with a rootstock (bottom) and scion (top) that produces the fruit. Dwarf and semi drawer for fruit trees are usually grafted and may be considered “dwarf” rather than miniature. Dwarf fruit trees are made “dwarf” by attaching them to roots that cause the tree to become smaller. Dwarf fruit trees MUST be grafted to another tree so that they become smaller. Dwarf fruit trees are small because they are forced to be small through graftage. Grafted peach tree with a graft union, sometimes called a “dogleg”. By grafting apple trees to another tree that doesn’t get as large, the apple tree will never grow large. It stays small; a “dwarfed form” of the same tree. Fruit from dwarf fruit trees have the same taste and size as the normal-sized tree. But the tree itself remains smaller; a dwarf version of the same tree. There are dwarf forms of Red Delicious, Fuji, Granny Smith, Gala and all other apple varieties. These are all grafted to a dwarfing rootstock.

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Baking Potting Soil to Rid Fungus Gnats

Leave a Comment / Sterilizing potting soil / xtremehorticulture

Q. I find it impossible to purchase a bag of potting or garden soil that does not contain gnats. This has been a problem with different brands, from local nurseries and home stores. How does one avoid this problem? I don’t care how expensive it is, nearly every potting soil has problems with fungus gnats.When they are in large numbers and houseplant soil they can damage young tender roots of growing plants. A. Fungus gnats (small flies coming from potting soil) are a very common contaminant in potting soils because many are not heat treated to kill them. Raw components are simply mixed together and not composted when it is finished. You will find this problem in nearly all bags of potting soils from expensive mixes to less expensive mixes. The best way is to raise the temperature of the potting soil to at least 140F for 30 minutes and kill them. Put the potting soil in a clear plastic back, moisten it slightly if it is dry, and let it “cook” in the sun for a few days near a south facing wall in full sun. Turn it over and try to bake both sides as thoroughly as possible. Another method is to put the potting soil in the oven and set the temperatures as low as possible, making sure it hits at least 140 thoroughly for 30 minutes. You don’t want the temperature much above 180F because it can harm the organic content of the soil. If you keep the temperature of the soil below 200° F, there will be very little smell associated with baking it.

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Plants (and other things) That Attract Bees in Desert Landscapes

Leave a Comment / Attracting bees to landscapes / xtremehorticulture

Q. I would like to plant some bee attracting plants this fall. I read that bee balm is excellent but that Vegas is not the best climate for it. Do you have some suggestions for plants in Las Vegas? A. When do you want the bees to come? It isn’t difficult to find plants that attract bees. It is more difficult to find plants that bloom at a time when you need to attract pollinators. Rosemary is a good plan for attracting honeybees because it blooms almost all season long, particularly during the winter months in warm locations. I like Rosemary because they are flowering and attracting bees at the same time when fruit trees are just starting to bloom. Plants are only one ingredient for a attracting pollinators like bees into the garden. A good winter plant for attracting them in the winter months is Rosemary. You need to attract honeybees into the yard starting in early February to help pollinate peaches, nectarines and apricots. Here is a honey be attracted to a fairy duster plant. The flowering time must correspond to the time when you need to attract these insects for pollination. Water If you put out some water, keep it clean and have a shallow landing area for them it will attract bees. When it starts to get warm, bees haul water back to the hive to keep it cool. Just simply putting out a birdbath near your vegetable garden helps pull them into your garden area. But remember to keep the water and birdbath clean. Don’t fill the birdbath with water. Leave an area for these insects to land, collect water and return to the hive. Or put some rocks in the birdbath that they can land on.You’ll see them trying to use swimming pools but often times they drown because there is no shallow area to collect water. Leaf cutter bees typically come out too late in the season to do much good in pollinating early season fruit trees but they can be great in the vegetable garden as long as you can tolerate the damage from them. Food Hummingbird feeders filled with sugar water attract honeybees. They need that the sugar for energy and will take this concoction back to the hive. The hummingbird feeder needs to be emptied, cleaned, washed and filled again with clean sugar water. Feeding honeybees sugar water isn’t the healthiest diet but it will attract them to the vegetable area. Some Tanglefoot on the support stake keeps ants out of the feeder.Sometime around late March or April leaf cutter bees will become active. They are great pollenizers but they come out fairly late in the spring. You can increase the number of solitary bees on your property by putting out places for them to lay their eggs like these Bee boxes. They are just 4 x 4’s with 3/8 inch holes drilled in them for the females to lay their eggs. Solitary bees like leaf cutters are very good pollinators. Bee balm, Monarda, will grow fine here. It just isn’t a desert plant so don’t treat it like one. Bee balm cannot be planted and cared for as you would, for instance, desert marigold, a true desert plant. Bee balm will need soil improvement at the time of planting and watered more often than plants like desert marigold. Many of the herbs like rosemary are great for attracting honeybees. Other herbs favored by honeybees include oregano and marjoram. During hot weather, honeybees like scavenging for water. They are constantly hauling water back to their hives to help keep it cool. If you have lots of plants flowering in the yard, then providing water that honeybees can haul may be a partial solution. Provide a shallow reservoir of water with a “landing area” so they won’t drown. Make sure the water is changed regularly so that it’s clean, like a birdbath.

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Why Does My Yellow Lady Banks Rose Have White Flowers?

Leave a Comment / White flowers on lady banks Rose / xtremehorticulture

Q. I planted three yellow Lady Banks roses on my south wall when I moved here 10 years ago. Two years ago, my neighbor planted a white, lady Banks rose nearby. This year I noticed white roses growing on my “yellow” Lady Banks rose. I thought these flowers might be from their plant but traced it back to the base of my vine. Will my yellow roses eventually all be transformed to white? How do you explain this botanically? Some lady banks roses are grafted onto route stocks that produce white flowers. Is this a miracle when white flowers appear? A. I wish we could declare it a miracle, submit it somewhere and have a party. But, unfortunately, it probably isn’t. What makes this observation even more interesting is that Lady Banks rose comes in two basic colors; yellow and white flowering selections. White Lady Banks rose On rare occasions, a totally different plant can grow from a mother plant. This is called a “sport” in horticultural terms. These are genetic abnormalities, a mutant if you will. Most mutants are not valuable, wasted time in evolution, but sometimes they can be valuable. Yellow Lady Banks rose One example is the nectarine. The fruit from a nectarine tree is basically a hairless peach. The tree is identical to a peach tree. If this hairless fruit had hair on it, we would call it a peach. The first nectarine, ever, was found by a farmer growing as a “sport” from a peach tree. Mutants like these can give rise to totally new types of plants which can become important commercially. If it wasn’t for this observant farmer, we wouldn’t have nectarines today. Back to your situation. Then how did these white flowers suddenly appear on a totally “yellow” plant? Unfortunately, the explanation is probably quite simple and not very “miraculous”. Notice that this sucker with white flowers on it is coming low on the plant, close to the rootstock. Lady Banks rose is grown commercially by grafting the Lady Banks part, called the scion, onto a different rose plant used for its roots; the rootstock. This rootstock is a totally different kind of rose flower but it’s roots that have desirable characteristics that can contribute to the survival of the scion plant. Lady Banks rose over the top of the wall In your particular case, the scion, the yellow Lady Banks rose, was probably grafted to Rosa fortuniana, a white rose commonly used for it’s very desirable traits as a rootstock. Rosa fortuniana shows excellent resistance to nematodes and a great deal of tolerance to poor soils. It is a very common rootstock used for roses planted in southern climates of the United States. These white flowers come from a “sucker” growing from this white “rootstock” rose. As it gets older, this sucker produces white flowers, quite a bit larger than flowers of the yellow Lady Banks, but an excellent rose in its own right just the same. Yellow lady banks rose used as a screen on a trellis behind some retail establishments. You can elect to prune these “white suckers” from the mother plant and keep it totally yellow or let these suckers grow and have a beautiful combination of white and yellow flowers on the same plant. Some pruning may be required to achieve a balance in growth between the two roses so that one does not dominate over the other.

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When to Change the Irrigation Clock and How Often

2 Comments / How much to irrigate and when / xtremehorticulture

Q. You mentioned increasing how often you water, not the number of minutes, as the growing season changes. When are these changes made and how often should they be watered? A. Irrigation schedules can be important but they can also cause problems if some flexibility in this schedule isn’t provided when the weather isn’t cooperating. This cool, wet spring was the perfect example. Irrigation Should Follow a Seasonal Pattern Scheduling irrigations should follow a seasonal pattern that increase the frequency of applied water as the season moves from spring to summer to fall. This is much easier to do than adjusting the number of minutes of applied water. These are daily averages of water use of plants in the Las Vegas Valley as they vary from month to month. The numbers 1 – 12 correspond to the months of January (1) through December (12).On top of each bar is the daily average of water use for the month in inches of water per day.Notice in June (6) and July (7), the hottest months, water use is 4/10 of an inch per day. While in January (1) and December (12), the coolest months, water use is 1/10 of an inch of water per day.This represents a 400% increase in water use from mid-winter to Midsummer. Basic fruit tree irrigation schedule for Southern Nevada First week of February (irrigate once per week) Last week of April – first week of May (twice per week) Midsummer, late May – June (three times per week) last week of August – September (twice per week) last week of October – November (once per week) second week of December (winter schedule, leaf drop, 10 – 14 days) Using the Soil Moisture Probe For Fine-tuning The concept of an irrigation schedule is sound but some hands-on judgment should be applied when irrigation changes are considered. These judgments help “fine tune” a schedule around unseasonal weather conditions. Knowing how much water is remaining in the soil is a critical hands-on judgment. It is impossible to look at the surface of the soil and know how much water is around the roots. A piece of equipment I have found valuable is a heavy-duty, soil moisture sensor. The one I like has a 24 inch stem and can be purchased online from stores like Amazon for about $70. I will put a link to it on my blog. Soil moisture probe with the moisture sensing device located at the tip of the probe. This is a heavy duty model that can be pushed into most desert soils without breaking. Push the probe into the soil slowly to get moisture measurements near the surface of the soil and deeper as it is pushed deeper into the soil. Moisture sensor is located at the tip of the probe. Measure soil moisture around trees at three to four locations for each tree and midway between drip emitters Heavy Duty 24 inch Soil Moisture Proble The moisture sensor is located at the tip of the probe measure soil moisture at three or four locations at each tree slowly push probe into the soil to root depth (2 to 8 inches) as you watch the meter meter needle should indicate more moisture as the probe is pushed deeper irrigation is needed when the average moisture level has dropped to “6” or below Moisture 8-10 No irrigation needed Moisture 7-6 Irrigate soon Moisture 5-6 Irrigate now Moisture 1-4 Reserved for cacti; too dry, possible plant damage Water in the soil is like the gas tank of a car Think of the soil surrounding fruit tree roots like the gas tank of a car. We fill a gas tank after we drive the car for awhile. When irrigating, use about 50% of this “gas” before filling the “tank” again. During the winter months, when fruit trees use very little water, we fill the gas tank infrequently. During the summer months when we are “driving around a lot”, fill the gas tank more often. Change the watering frequency, not the number of minutes.

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Where to Get Woodchip Mulch for Landscapes in Southern Nevada

Leave a Comment / Woodchip mulch benefits / xtremehorticulture

Q. I have been very pleased with the woodchip mulch I got from the University Orchard and am using around my fruit trees. I need more of it in larger quantities. Can you recommend where I can get it? A demonstration on fruit tree growth using woodchip mulch applied to the surface of desert soils after planting clearly showed the benefits that this organic mulch gives fruit trees planted in desert soils after only one season of growth. The community mulch pile is a free source of wood chips that are diverted from entering public landfills, buried in the desert. Community mulch piles are located in North Las Vegas near the RC airport and shadow Creek High School as well as in the southern part of the Valley just south of the airport near Windmill and 215. For more information about how you can get this mulch, call the Master Gardener helpline at 702 – 257 – 5555 A. I started using local woodchips as a surface mulch around fruit trees back in the late 1990s at the University Orchard in North Las Vegas. I agree. The health of the trees when woodchip mulch is used surrounding them is like the difference between night and day. Woodchips slowly decompose into the soil surrounding these trees over two or three years time, thus dramatically improving desert soil. When I was looking for woodchips in the late 1990’s to supply to the Orchard as a mulch that was free from palm (slow breakdown) and mesquite wood (thorns), First Choice Tree Service jumped at the chance of working with us on this project. They provided a beautiful mulch free of both of this type of wood and clean. They rearrange their pruning schedule so they could deliver a clean supply of mulch for our fruit trees. These woodchips are sourced from local trees “rescued” from the landfills. They are recycled rather than buried in the desert. I do not allow palm trees or mesquite wood in this woodchip mulch mix because of the dangerous thorns of the mesquite and the difficulty in getting palm wood to decompose. The benefits from using woodchips as a surface mulch around fruit trees and landscape plants will be seen the first year after it’s applied around the trees. These woodchips can be picked up free of charge from the University Orchard and North Las Vegas or the Cooperative Extension office just south of the airport. For more information call the Master Gardener helpline at 702–257–5555. The primary tree company in Las Vegas responsible for this effort is First Choice Tree Service. It is worth giving them a call to see if they can deliver it in large quantities.

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All Plants Moved to a New Location Suffer from Some Sort of Transplant Shock

Leave a Comment / recovery time, Transplant shock, transplanting / xtremehorticulture

Q. In early February I moved a small Ruby Red Grapefruit tree into a half barrel full of prepared soil. I made sure the roots did not dry out when I moved it. I pruned the top back best I could. What leaves were still on eventually fell off. It is slow to put on new growth compared to my other citrus trees. Ruby red grapefruit moved to a container, transplanted, with the top cut back to compensate for root loss during transplanting.New growth will occur first on existing buds. If the tree must form new buds because they were all removed when they were pruned, the tree will take longer to recover. Ruby red grapefruit stem cut with a thumbnail and shows that the stem is still alive and healthy because it is green under the “bark”. A. Your tree is experiencing “transplant shock”. No matter how careful we are when moving a plant, roots get torn, they dry out, and the roots must readjust to their new environment. Sometimes these adjustments are minor. Sometimes they are major. Minor adjustments may be so short in time that the tree seems like it needed no recovery time at all. Major adjustments take longer to recover. During major adjustments or recovery time, the tree does not grow at all but just sits there seemingly like in frozen animation. The tree is alive, but it isn’t growing. You can see that it is still alive by doing what you did with your thumbnail. This is because the tree must make other adjustments to the damage that you can’t see. Once moved, the new plant must take some time to ‘repair’ these torn and damaged roots first before it can resume normal growth again. Sometimes we say that the tree is reestablishing its “root to shoot ratio”. If these adjustments are minor, transplant shock is hardly noticeable. If these adjustments are major, it can cause long delays in resumption of new growth or the plant can die. How quickly the tree recovers depends on how it was pruned after moving it. Shearing the entire plant causes the tree to recover more slowly. This is because all of the buds for a quick growth response are removed when the plant is sheared. Selectively removing branches aids the plant and recovering more quickly.This is because buds that will grow quickly are left remaining on the tree. Most likely your tree will recover soon. Keep it out of intense sunlight until you see signs of recovery. Then move it back into full sun. Make sure the tree is staked so the roots don’t move so that they must reestablish again. Keep the soil moist but not wet to minimize root rot. Sometimes we panic and water too often thinking we are trying to help the tree. This can actually cause problems. Here’s how to minimize transplant shock. 1. Move as much and as many of the roots as possible. Moving all of the roots is not possible when transplanting established trees. 2. Cut back the top. By pruning the top back we readjust the root to shoot ratio in a positive way and encourage the top to grow back more quickly. 3. Amend the new soil around the roots to be as similar to the old soil, or better, as possible. 4. Stake the new tree. Keep the roots from moving around too much in the new soil. Stake the plant so the roots do not move. The top can move but the roots should not for one growing season. 5. Add phosphorus fertilizer to the new hole. Phosphorus fertilizer helps routes to grow and establish in their new soil. 6. Keep the soil moist but do not keep it wet. Roots need air to breathe. Add enough water to the soil to keep it moist but not overly wet which drives out the air around the roots. 7. Wait. New root growth it takes a while. Be patient. As soon as roots become established in the soil, the top of the tree will show signs of growth.

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