Q. I recently saw an article about cactus in the Las Vegas newspaper (not one of your articles, however.)  The author was discussing how to plant a cactus, especially when removing it from its current pot and placing it into a larger one. He advised the person asking the question to always plant the cactus “with its front facing the sun.”  How do you tell which is the front of a cactus?  Darned if I can tell when looking at mine. Barrel cactus with its front facing away from you…or is it backwards? Hmmm…. Ahh….now this cactus looks like it has a front! A. That’s a good one! I have no idea what the front of a cactus is either. I guess I could make some wisecracks about it. But I think you realize the author is just telling people to orient the cactus the same side toward the sun to reduce problems from sunburn.

Viragrow Delivers! : Properties and Uses of Whitewash Paint: This standard includes guidance on the preparation of whitewash paint. It also includes general information on its composition, cha… Viragrow Delivers!

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Q. Have you done any experiments with gamma rays and X-rays applied to seeds attempting to mutate them into something different? Totally curious if this is at all done or just a neat idea. A. Giving seeds some sort of radiation to mutate them into something better is a little bit like taking a Hyundai and smashing it into a brick wall hoping to get a Mercedes. This kind of research was tried by scientists not that long ago without much success. The mutations were all over the place. Manipulation of plants is focused on its DNA or “genes”. When radiation is given to seeds, we do not know which part of the DNA, if any, is changed until they are grown. Just like the Hyundai example, the results can be highly variable. Genetic engineering, on the other hand, is precise. If genetic engineering is successful, scientists must precisely understand the genetic information inside the plant. Specifically, they must know exactly which gene controls which plant function. Genetic engineering changes a specific gene which in turn causes a plant to change, hopefully, in a predicted way. This new or “changed” gene provides the plant with different guidance than before. When new genes are spliced into existing DNA, the plant responds differently according to which gene was changed. The result is a mutation but scientists have a much more accurate guess as to how this new plant will act. Genetic engineering causes the “Hyundai” to become something different; maybe a pickup truck. This newer form of the same plant, scientists hope, will be an improved version of the old one. People who are skeptical of this type of science, cautious or opposed to genetic engineering, are concerned this “new” plant may be something dangerous to human health, dangerous to other plants, to our environment, or cause a result scientists have not anticipated. An alternative point of view from the New York Times

Q. When should I put tulip bulbs in the fridge so that they bloom on Easter or a few days earlier. Can you please help me? I want a nice table centerpiece. A. Getting tulips to bloom precisely at Easter is difficult for a homeowner because they frequently do not have enough information about the tulip or a precision growing environment. Commercial growers using greenhouses get plants to bloom precisely on a specific date by selecting known varieties and growing them at precise temperatures. Some plants like mums and Christmas cactus, require controlling the length of darkness or the application of growth regulating chemicals at specific times. Tulips are a little easier. Most tulip varieties bloom in 4 weeks if the temperature is kept constant at 60F. Plants grow faster or slower depending on temperatures. Plants grow faster in warm weather and slower in colder temperatures. If tulips are grown ten degrees warmer, 70F, subtract a week. If grown 10 degrees cooler, 50F, add a week. A few varieties may take 5 to 6 weeks to bloom at 60F. For precision blooming, it’s best to know the variety of tulip being grown and how many weeks it takes to bloom. Some flowering plants require cold temperatures to bloom. We oftentimes have enough outside cold temperatures for tulips during winters in the Las Vegas Valley if they are planted on the north side of a building and in the shade. But it depends on the variety.  To vernalize tulips (subjecting the bulbs to cold temperatures so they produce flowers) the bulbs are placed in a refrigerator 12 to 14 weeks. They will grow a little bit, slowly, at this temperature. Some varieties of tulip require fewer than 12 to 14 weeks. Some tulip bulbs are available pre-chilled.  Here is how I would do yours. Stick the bulbs in the refrigerator, upright, in slightly moist potting soil for 14 weeks.  At the end of 14 weeks, put them at room temperature five weeks before you want them to bloom. If they are growing too fast, grow them colder; put them outside in the shade on the north side of the house to slow them down. When they are back on track, bring them back indoors.  Water them when needed but don’t keep the bulb wet. The bulb can’t be dry either. It can lose roots that way. Use a soil moisture meter to judge when to add water. Fertilize lightly once a month with a water soluble fertilizer during warm temperatures.  No guarantees it will be exactly on the date you want but it will be close.

Q. I am putting in 30 more wine grape vines. I was thinking of using chat, crushed rock, for mulch rather than wood chips. What do you think? A. The idea of using rock mulch, rather than wood chips, addresses a controversy among wine grape growers. Some growers of high quality wine grapes believe that wine grapes must “struggle” to produce a good quality wine grape. They believe the best wine grapes come from poor soils and a limited water supply. Jerry Nelson with John Arellano from Duarte Nursery in California Wine grapes without any kind of mulch growing in raw desert soil near Amargosa Valley, Nevada. Jerry Nelson’s vineyard. The hot desert, with nighttime temperatures around 90° F or more during harvest time, is thought to produce a poor quality wine grape. It is believed that nighttime temperatures should be cooler than this during harvest. Grape harvesting event I put together for Slow Food Las Vegas at the Gehring Vineyard in Amargosa Valley, Nevada. Few people believe that a good quality wine grape can come from this type of environment. This may not be true about table grapes. Some of these same producers believe that soils for wine grapes should not be full of nutrients. Adding compost or soil amendments that improve the soil, they believe, produces a grape without intense flavor typical to the variety; a poorer quality grape. I might point out that the flavor attributes of wine grapes is valued much higher than table grapes. Roger Gehring and I at his orchard in Amargosa Valley, Nevada, several years ago when his vineyard was first established. The verdict is still out but I believe that wine grapes struggle enough in our climate and soils without additional stress from poor soils and a lack of water. I have seen wine grapes grown in backyards in our climate without soil amendments. The soils around the home, in these cases, was “fill dirt” specified by the contractor. These did, generally, poorly. I have seen wine grapes grown in our climate in native soil, with no organic surface mulch such as wood chips. These did much better. I might point out that in cases like these the soil was a good agricultural desert soil, not “fill dirt”. Wine grapes at the UNCE MG Orchard in North Las Vegas, Nevada showing 3 to 4 inches of wood chip surface mulch. I have concerns about growing wine grapes in home landscapes if the home was surrounded with fill dirt. I believe this soil should be amended at the time of planting and the soil surface should be covered with an organic mulch, such as wood chips. I am concerned that applying rock mulch, like chat, to its surface will lead to future problems for wine grapes and many other landscape plants sensitive to poor soils and not intended for our climate.

Viragrow Delivers! : Rejuvenate Soil Mix is Rejuvenated by Mid-January!…: Part of my consulting work is with a soil mix company in Las Vegas called Viragrow ( www.Viragrow.com ). When I started with this company …

Q. My Grandfather had fig trees in Southern California. They were the most incredible figs.  He would cut it back to a stump every winter. Every year it would have tons of fruit.  He would pick a lot of it early in order for the other fruit to get big and ripen. He claimed that planting fig trees close to a house caused the roots to grow under the house and cool the roots. His trees were huge.  In the desert of Moapa Valley, we have several fig trees that are old, but they are small, dry, the leaves are burned and they have been stumped, but only every 2 or three years, not every year like my Grandfather did. The trees are fed water with a slow drip system and there is mulch on the ground around the trees.  But the fruits are small and terrible! Many fruits just dry up and drop. They have no shade and are hit with direct heat. Suggestions? Fig tree being grown without enough water will look like it doesn’t have enough, sparse canopy, little new growth and small scorched leaves and will not produce fruit. A.  Everything I have seen so far regarding figs and the production of fruit in the desert is focused on water. I have grown over 15 varieties of figs over a period of 25 years in the Mohave Desert and all of them have been productive. Problems with the figs are few.  Dried Fruit Beetle Dried fruit beetle The first problem I encountered was the dried fruit beetle. This insect would climb inside the fruit of the figs and cause them to sour. The insect carried with it a bacterial infection of the fruit that caused this problem. If you look at the base of the fig fruit, there is an opening. This opening can be shut or open depending on the variety of fig. Those fig varieties with it open had a bigger problem with the dried fruit beetle than those with fruit openings that are shut. The simple solution is to make sure that fallen fruit and fruit still hanging on the tree after it was mature was collected and put into sealed containers. Dried fruit beetles reproduce in rotting, over mature fruit and spread into soft fruit. Metallic Green June Beetle The next problem I had is with the green metallic June beetle. They love fig fruits in particular the white or yellow types like Kadota. They attack and feed on this fruit but the presence is gone in a short time during the summer. I ignore them. Green June Metallic Beetle Fig Mosaic Virus The last problem I have encountered is fig mosaic virus. Not a huge problem but it gets into all of the fig trees eventually. Probably spread by insects from tree to tree. Doesn’t hurt the tree and it doesn’t hurt the fruit much so I ignore it. Fig Mosaic Virus Lack of Water The really big problem with figs growing in the Mojave Desert is lack of water. Fig trees are big users of water. The tree can grow and look fine with a moderate amount of water. But if there is not enough water the fruits will either drop from the tree early or they will be small and hard, not edible.  If fig trees get enough water for new growth it is still possible they will not produce a decent crop of figs. I have had many reports of people growing fig trees with small, hard fruit that are just simply lousy. Until I see something different, I believe this is a lack of water. You can apply small amounts of water daily and still not give the tree enough water for good fruit production. It is not a question of how often the tree is watered but more it is a question of how much water the tree is given in a single application. In the middle of summe middle trees up to 10 or 12 feet tall may require 90 – 100 gallons of water each week. I have found the best way to irrigate fig trees is by filling a basin beneath the tree that is 4 to 6 inches deep, 2 to 3 times each week during the summer. This can be done with the hose or with an irrigation bubbler. If drip emitters are used, there must be enough emitters and they must be on long enough to deliver this amount of water. This could be hours depending upon the number of emitters and their size.