Q. Should I be saving potting soils from seasonal purchase plants? I have been saving soils for years. Should the soil be thrown away at some point. Garden Gourmet potting soil from Viragrow. It is made lighter in weight for containers or pots. Soil amendments like perlite, peat moss and even compost can be lighter in weight and hold water or nutrients. A. Potting soils can be saved and reused for years. They can be valuable when added to our soils because of the “organics” they contain. These never go bad. But these “organics” don’t contain any plant nutrients and they can harbor diseases if used during their first few months after saving. Rid this aggregated potting soil of any diseases it might contain by moistening and then placing it inside a clear plastic bag. Place this clear plastic bag full of potting soil in the summer sun for a few days. When it reaches a temperature of 180°F for 30 minutes or more, it will be sanitized of any diseases. Once sanitized, they are ready to reuse.

Q. We have two 12-year-old Texas Sage shrubs concealing the street mailboxes. Within a month this past summer, they were dying back rapidly. The dieback spread over both plants. The irrigation hasn’t changed. Any idea what could be causing this?  Not readers plant. Showing collar rot. The top dies because its choked….rotten. A. My explanation follows the KISS principle. Texas Sage, a Chihuahuan desert native, has roots that die if watered too often. If the main stem or trunk of this shrub stays wet, this could cause it to die. My guess this is a trunk/root disease caused by watering too often. This disease moves with irrigation water and can spread easily between nearby plants. Put Emitters Close When First Planted When first planted, the drip emitters must be close to the plant. I like to put them up to about 12 inches during the first year. They should be moved, and more drip emitters added, as the plant gets larger in the second or third year. They are moved to about 12 to 18 inches away from the trunk at this time. This practice does not change the irrigation frequency but changes how much water is applied and where it is applied. A larger area under the plant is watered to compensate for its increased size.             Move the drip emitters away from the trunk or main stem to a distance of 12 to 18 inches from its trunk. This should be done when the shrub is 2 to 4 years in the ground. At the same time, add more drip emitters and redistribute the emitters so that they irrigate half the area under the enlarged plant canopy. This gives the plant more water, distributes the water to a larger area because it’s larger and reduces the chance of trunk/root diseases of susceptible plants.

The major mistakes made when planting are not making the planting hole wide enough, digging the hole extra deep when it’s not needed, planting too deeply, and watering the plants too often after planting. The amount of “organics” in a soil can be “eyeballed” in many of our soils by its color. When a soil is darker in color, it means it has more “organics” in it. The Mojave Desert soils in Las Vegas have generally have no organics in them at all. This is why we add organics to the soil, oftentimes in the form of compost, to raise the level or its content. This is Garden Soil Mix from Viragrow and used for planting. I like deals Buying a large tree in a box and getting it planted for free is a good deal! Just have it done right. Beware. Numerous people have complained the “planting crews” dug the hole only wide enough to fit the box in the planting hole. After that a little bit of mulch is mixed with the soil, watered in, and called good. That’s no deal. The tree will decline and maybe die in a couple of years because of these poor planting techniques. Yellowing leaves like in this bottlebrush can be a sign that the organics in the soil is running out due to its mineralization in a few years by rock mulch. Some plants dont like rock mulch but want a soil that has at least 2% organics in the soil. This soil under the rock probably has less than 1%. Planting Right If these deals are too good to pass up, then make sure the planting hole is at least three times the width of the box. Pay planting crews extra to do it the right way if you must. The hole doesn’t have to be dug extra deep, but it should be dug wide. It’s okay to use the soil taken from the hole for planting, but first mix it with about one third by volume of compost. If a normal compost is used, make sure to mix in some fertilizer with the soil used for the planting hole. “Rich” composts don’t need extra fertilizer in the soil mix. Use this soil mixture for filling the planting hole around the rootball and then water it in with lots of water. Water it like this for two days in a row. Make sure the tree is watered thoroughly at planting time., To force the water deep in the planting hole, construct a “well” or “moat” 4 inches tall just above the planting hole and fill it with water. Deep Holes – No, No, No The planting holes shouldn’t be super deep. (unless there is a problem with drainage which is more rare than you might think). If a hole dug in the soil drains water overnight, there is no drainage problem. However, if the water is still in this hole by morning, then there is a drainage problem and other planting methods are needed. But poor drainage is not frequent in most of our landscapes. The soil around the tree in the box or container should be “milk chocolate” in color when wet and the same level as the rest of the landscape soil when everything is finished. The tree should not be below or above the surrounding soil when finished. Make sure the soil is wet when planting. Why Stake Staking trees and shrubs can be very important in getting the roots established during the first year. The stakes that come with 5 and 15-gallon plants are usually good enough to reuse if cut free from the plant and pounded into the solid soil at the bottom of the planting hole so the plant roots can’t move. The purpose of staking is to keep the plant roots from moving, not necessarily the top of the plant. The top of the plant should be free to move in the wind.

Q. I live in a climate very similar to Las Vegas; USDA Zone 8B. I planted a 1-gallon Texas ranger shrub two weeks ago in sandy/stony soil, watered them with about 2 gallons daily for 10 days. After, I put a 1-inch deep, bark mulch on the soil surface. Now, three weeks later, the leaves are yellow, brittle and crunchy on the lower stems with curling leaves on the top. I think I overwatered, but I’m not sure. Honeysuckle crown or collar rot. A disease of plants that are watered too often. A. Yes, sounds like they were watered too often and now probably “root dead”. Watering too often has caused the leaves to yellow, brown, and get crunchy. After the initial watering, let the soil drain water and give the plant roots air. The plant roots drowned because the plant was continuously watered. Watering the plant with 2 gallons is about the right amount after planting. It could even be more than that. But after that, schedule the irrigations to skip at least one day so the water drains from the soil in the roots can “breathe”. This time of year in early spring, probably once or twice a week watering is enough, even for a sandy/rocky soil! The soil around the roots was amended so it will hold water. The bark mulch on top of the soil gives you about a day extra between irrigations. The bad news is that the soil surrounding the overwatered dead roots is probably “contaminated” with root disease problems. It could be replaced I suppose but I suggest digging a new hole for planting, at least 2 or 3 feet away from the old, contaminated hole. Dig the hole 2 to 3 feet in diameter for a 1-gallon plant. It doesn’t have to be deep, but wide. Next, mix the soil taken from the hole with about one third compost. Wait till the last minute and finally remove the plant from the container. To do this, turn the container over and let the plant slide onto your hand. Lower the plant into the hole, holding it by its rootball, and place it so it’s resting at the bottom of the hole.             As you are pushing this mixed soil back into the planting hole, everything is wet. Make this planting soil a “slurry” by adding water slowly to the whole with a hose so this “slurry” flows and fills all the gaps around the rootball. You should see air bubbles surfacing from this slurry. Build a moat, 2 foot wide, around the plant to force excess water down and not run off the soil surface. Fill this moat with water. Do this twice. No more than twice.             If the plant came with a nursery stake, push it into the wet, solid soil at the bottom of the hole next to the plant and re-tie the plant to the stake with stretchable, green nursery tape. This immobilizes the plant until the roots have anchored it into the soil. Remove this stake at the end of the growing season.             If you buy 5-gallon plants, use around five gallons of water when irrigating with the timer. If you buy 15-gallon plants, plan on around 15 gallons of applied water when irrigating. What killed the plants is watering too often, not the amount applied.

From http://plant-disease.ippc.orst.edu/disease.cfm?RecordID=40 Vegetables like beans can have crown rot (collar rot) when planted in cold soils. Different varieties of beans will show different tolerances to cold soils and collar rot development.   Cause: Phytophthora cactorum and other species, a soilborne fungus-like microorganism. Crown rot is a disease of the rootstock portion of the tree; collar rot is a disease of the scion portion. Both are serious diseases of apple and other orchard trees in British Columbia, Washington, and Idaho, and have become a problem in Oregon orchards with clonal rootstocks, principally Malling Merton 106. Crabapple can also be infected. The fungus survives primarily as oospores in soil, organic debris, or infected tissues. Oospores produce a swimming spore stage (zoospores) when soils are at or near saturation. Zoospores swim to and infect roots. Movement within roots to the root crown is greatest between pink bud and shoot elongation. Apple crown rot in Lebanon   Symptoms: In early fall, an affected tree shows bronzing, purpling, or yellowing foliage of one or more limbs, accompanied by bark reddening. There is a reduction in the size of leaves and terminal growth. Examination at the root crown or collar after scraping away the soil reveals dead bark. The cambium will be orange-brown to red-brown, eventually becoming dark brown instead of white. A distinct margin may separate healthy from infected tissues. In many cases, the tree may be completely girdled before its condition is noticed. Fire blight symptoms may be similar when confined to the rootstock. ‘Antonovka’, ‘McIntosh’, and ‘Wealthy’ apple seedlings and M9 clonal rootstocks have shown high resistance to collar rot. Moderately resistant: MM111, M2, M7, M26, ‘Golden Delicious’, ‘Delicious’, and ‘Rome Beauty’. Susceptible: MM104 and MM106.A   Cultural control: Plant on a raised bed to help keep water away from trunks. Avoid overirrigation. During summer, examine root crowns of trees for collar rot and scrape off diseased tissues. Leave root crowns exposed to the air until late fall. Avoid wounding root crowns. If a wound is made, keep it uncovered and open to the air for the remainder of the season. Chemical control: Apply before symptoms appear, especially in orchards favorable for disease development. No chemical will revitalize trees showing moderate to severe crown rot symptoms. Although resistance has not been reported, alternate materials so resistant fungi do not develop quickly. Agri-Fos at 1.25 to 2.5 qt/A. Do not combine with a copper-spray program for control of other diseases. 4-hour reentry. Aliette WDG at 2.5 to 5 lb/A. Spray foliage to run off. Follow manufacturer’s directions for timing of spray. Do not apply within 14 days of harvest or more than 20 lb/A per season. Do not combine with a copper spray program for control of other diseases. Phytotoxicity may result if applied within 1 week of a copper spray. 12-hr reentry. Fixed copper products. Use 4 gal solution as a drench on the lower trunk of each tree in early spring or after harvest. Do not use if soil pH is below 5.5. Not considered organic since application is to the soil. Champ Formula 2 at 2.75 pints/100 gal water. 24-hr reentry. Copper-Count-N at 4 qt/100 gal water. 12-hr reentry. Cuprofix Disperss at 5 lb/100 gal water. 24-hr reentry. Kocide DF at 4 lb/100 gal water. 48-hr reentry. Nordox 75 WG at 2.5 lb/100 gal water. 24-hr reentry. Fosphite at 1 to 3 quarts/A. Do not use copper products within 20 days of treatment and do not use spray adjuvants. May also be injected into trunk. 4-hr reentry. Phostrol at 2.5 to 5 pt/A. 4-hr reentry. Ridomil Gold SL at 0.5 pint/100 gal water. Apply diluted mixture (based on trunk size measured at 12 inches above the soil line) around each tree trunk. Apply once at planting or in spring before growth starts. Apply again in fall after harvest. 48-hr reentry. References: Jones, A.L. and H.S. Aldwinkle. 1990. Compendium of Apple and Pear Diseases. 1990. St. Paul, MN: APS Press. Content edited by: Jay W. Pscheidt on January 1, 2008 Vegetables like beans can have crown rot (collar rot) when planted in cold soils. Different varieties of beans will show different tolerances to cold soils and collar rot development.   Cause: Phytophthora cactorum and other species, a soilborne fungus-like microorganism. Crown rot is a disease of the rootstock portion of the tree; collar rot is a disease of the scion portion. Both are serious diseases of apple and other orchard trees in British Columbia, Washington, and Idaho, and have become a problem in Oregon orchards with clonal rootstocks, principally Malling Merton 106. Crabapple can also be infected. The fungus survives primarily as oospores in soil, organic debris, or infected tissues. Oospores produce a swimming spore stage (zoospores) when soils are at or near saturation. Zoospores swim to and infect roots. Movement within roots to the root crown is greatest between pink bud and shoot elongation.   Symptoms: In early fall, an affected tree shows bronzing, purpling, or yellowing foliage of one or more limbs, accompanied by bark reddening. There is a reduction in the size of leaves and terminal growth. Examination at the root crown or collar after scraping away the soil reveals dead bark. The cambium will be orange-brown to red-brown, eventually becoming dark brown instead of white. A distinct margin may separate healthy from infected tissues. In many cases, the tree may be completely girdled before its condition is noticed. Fire blight symptoms may be similar when confined to the rootstock. ‘Antonovka’, ‘McIntosh’, and ‘Wealthy’ apple seedlings and M9 clonal rootstocks have shown high resistance to collar rot. Moderately resistant: MM111, M2, M7, M26, ‘Golden Delicious’, ‘Delicious’, and ‘Rome Beauty’. Susceptible: MM104 and MM106.A   Cultural control: Plant on a raised bed to help keep water away from trunks. Avoid overirrigation. During summer, examine root crowns of trees for collar rot and scrape off diseased tissues. Leave root crowns exposed to the air until late fall. Avoid wounding root crowns. If a wound is made, keep it uncovered and

Q.  I live in the Anthem community in Henderson NV at 2900 feet and have a large variety of plants watered with drip emitters. I typically fertilize three time a year with a local nursery product. I also apply EDDHA iron chelate as needed if a shrub shows signs of yellowing. Comments? One fertilizer application in the spring of each year is enough for most landscape plants. Some exceptions are lawns, vegetables, annual flowers and specialty shrubs like roses. A.  Mineral fertilizers for home landscapes are all the same, whether you get them from a local nursery or not. I select a mineral fertilizer based upon price and the three numbers on the outside of the bag. This is called a “starter fertilizer”. Why? Because the middle number, phosphorus, responsible for helping new roots to grow is highest. Phosphorus also helps promote flowering so it is also used as a rose fertilizer and tomato fertilizer. The last of the three numbers, potassium, should always be high. The first number, nitrogen, encourages growth and greening of the plant and disappears with watering. The middle number, phosphorus, encourages flowering, rooting and sticks around in the soil longer after an application. If there is any fertilizer needed by plants later in the year it’s the first number, nitrogen. Blood meal, fertilizer made from the blood of animals, is high in nitrogen; usually 12%. It also has iron in it but the numbers quoted for this fertilizer when sold as a mineral fertilizer is 12-0-0.  It is not “organic” unless it carries the organic label. Even though it is made from blood, it is not considered an “organic” fertilizer. One application of fertilizer in the early spring of each year is all that is required for most landscape plants. Exceptions are lawns, vegetables, and “show plants”, like roses that produce a show of flowers to enjoy. Even fruit trees grow well with one application of fertilizer in the spring of each year. Winter tender plants, like most citrus and bougainvillea, are fertilized only once in the early spring, avoiding fertilizer applications after the middle of summer. All that being said, it’s always best to repeat applications of fertilizer in small amounts all through the growing season. It’s not necessary, but according to research it’s best. this is the selling point made for fertilizer injectors like EZ Flo. EZ Flo fertilizer injectors are not really fertilizer vernri type fertilizer injectors rather than the very expensive but very exact fertilizer injectors. Theas types of injectors are exact enough for most homeowners but may not be exact enough for commercial greenhouse growers who need more precise application of chemicals to the irrigation water. For plants that like continuous feeding such as vegetables and “show plants”, I like to use rich compost as a fertilizer in the beginning of the year and then follow up with very light nitrogen applications the remainder of the year when needed.

Q. I moved here a year ago and have yet to figure out what my palm tree needs to thrive.  It gets plenty of water. I located and uncovered the drippers to make sure it was getting enough water and even moved some plants away from it so it got more water. Palms endure the heat. Some not so much the wind but they love the heat. They also love water. I consider palms to be “oasis” plants. When you find fan palms growing in the desert they are near surface water like here in Warm Springs, Nevada, or near an oasis. Mark my words. When you see palms growing in the desert I will bet you $10 you will also find water. A. Palm trees growing in the desert are “oasis plants”; they need to grow near water but not in it. They like to be surrounded by other plants that also need water. A big mistake to make with palm trees is to grow them alone, out in the middle of nowhere, and surround them with rock. Growing them alone, in full sun, and surrounding them with rock is asking for a multitude of different problems. Many palms are quite large. They may be cute when they are small but when they get larger…watch out! A second problem with most palms is their mature size. They are cute to look at when small, but all the palms get larger as they get older. Their growing size forces homeowners to pay more for pruning, and possibly removal, as these trees get larger. Mediterranean fan palm and Windmill palm look similar except the Windmill palm is much slower growing and doesn’t get wider like the MFP does. This is because it “suckers” from its base. It can get quite wide if it is not controlled as this one is. Probably the two palms that are the best choices for smaller residential lands  capes are the Windmill Palm and Mediterranean Fan Palm. The Mediterranean Fan Palm can be put into hot windy locations but requires pruning as it gets older. The pruning mostly focuses on keeping it from getting wider. The second choice is the slow-growing Windmill Palm. Windmill Palm should be placed on the East or north side of a landscape out of the wind. Both should be surrounded by other plants and woodchips rather than rock. This is a windmill palm. Lets see it in five years when the organics in the soil are gone and the rock has impacted the landscape of this “oasis” plant.

Q. I live in Summerlin in Las Vegas and have a small vegetable garden that I started this year. My first season has been erratic. I had four tomato plants; one of them gave a good amount of tomatoes other three just one or two through out the whole season. Pepper plant had no peppers. I had six bell pepper plants and got two bell peppers out of it. Out of two eggplant plants,  I got one small eggplant. I have a Myers Lemon tree that was planted 18 months ago and there is one lemon on it. My old tree at my old house used to be full of lemons. What may be the reason for this? Bill Stillman and his pomegranate windbreak in Bullhead City, AZ. You dont want to stop the wind, just slow it down. A. Once the soil has “settled down” in your garden and starting to get productive then it’s a matter of using the right vegetable varieties. I have attached a vegetable primer for growing vegetables in the desert written by Dr. Sylvan Wittwer who was a vegetable specialist at Michigan State University until his retirement. He lived in Logandale, Nevada for about 8 years and he wrote about his vegetable production there. I consider it to be probably the best source of vegetable growing information in southern Nevada. He recommend some old-fashioned varieties that are traditional standbys and I would suggest that you stick with those first.  As you introduce other varieties into your garden stick with some of the tried and true varieties that Dr. Wittwer recommends in this publication and introduce newer ones slowly and see how they do. Be careful about using seed from Lowe’s and home Depot unless you know the variety. Don’t assume that anything will grow here. It won’t. Some produce better than others here and some don’t produce much of anything in the desert. Selecting the right varieties are important! As far as your lemon tree goes it really is very dependent on the location of the tree in the yard, the microclimate that it’s in and spring weather. You might have had an exceptional spot at your old house. The most devastating weather factor for gardens and fruit trees is wind. If you have wind affecting your garden and your fruit trees then good luck with quality and production. It will be erratic at best and very dependent on the weather.  The best food is produced on the leeward side (side on the opposite side from the prevailing wind) . The circles represent zones of influence by the windbreak. the inner oval is five times the windbreaks height. This is the strongest “zone of influence’ impacted by the windbreak. The second outside half oval is 20 times its height. This area is still influenced but not as strongly. The best vegetables and fruit are produced on the leeward side of a windbreak or at least something that slows the wind down considerably. Consider chain length fence and PVC slats or temporary fencing such as reed mats that can help slow the wind down if yours is a windy location. Use screens that are about 20% porous to the wind.  Remember the importance of pollinators and plant things in your yard like Rosemary for instance or lavender or even a bird bath full of clean water that will attract pollinators all through the growing season. Plants that bloom all the time, like this rosemary, is a good choice to attract pollinators during bloom time. Incorporate these near your fruit and vegetable gardens. Fruit trees take a couple of years to get going so have some patience in the meantime.

Q. Which varieties of grapes are the best to grow in the Las Vegas valley? Zinfandel, one of the warm weather wine grapes, does very well in the desert. Zinfandel grape juice is not just for wine. It makes a wonderful and tasty jelly or juice. A. The best choices, or varieties, for grape growing in southern Nevada are those grapes which prefer to grow in hot weather. Recognize that grapes are grown for fresh eating (often times seedless) and those grown for their juice, such as wine grapes. Some examples of table grapes that grow well in hot weather include Thompson Seedless, Flame, Concord, Fantasy and Black Monuka. Others may also be a good choice, but these should get you started.             Juice or wine grapes that can be grown for their juice for making wine or jelly include Zinfandel, Muscats, Syrahs, Grenache, Barberra, and many others. I would be very careful growing the so-called “cool season grapes” such as the Cabernets, Pinots, Gewurztraminer, Merlot, and others. That being said, I have had good luck growing a few of the so-called cool weather grapes such as Pinot Noir.             Bottomline, check to see if they are warm season grapes or not. If they are, your chances of success are better than the cool season grapes.

Q. Last spring I planted two Early Girl tomatoes. In the middle of July, I cut them back to about 8 inches and they come back and give me a second crop in the fall. They usually die in the middle of December but not this year! Should I replant this spring with new plants? Tomato fruit the day after a hard freeze. Tomato fruit are damaged at temperatures around 45F, an effect on tropical fruit called chilling injury. These temperatures were at freezing,,,below 32F for just 30 minutes. A. Not necessary to replant. Tomatoes are a perennial crop that can get several years old in the tropics and are still productive. They will continue to be as productive as young plants if pruned back again this spring like you did before. The big advantage of existing plants is in their established root system. They don’t have to expend energy to reestablish roots. This means the tops will grow faster and be productive. Tomatoes prefer temperatures from about 65°F to 95°F. It’s just cold for these warm weather vegetables right now. Chilling Injury Chilling injury can happen to some tropical plants when temperatures drop below 45 to 50F. Think banana in a refrigerator. They dont freeze but they dont like it and the tissues are damaged. For banana, it turns brown. Never put tomatoes in the fridge unless you have to. They will get chilling injury. Not as as obvious as banana but it damages the fruit. Generally speaking, fruit is more sensitive to chilling injury than the plant but chilling injury can damage some plants.  How to Prune Tomato Clean and sanitize your garden shears and cut them back to about 8 inches again in late February or early March. Cut them about a quarter inch above a leaf. You can do it anytime you are confident temperatures are starting to warm up again. Add fresh compost, water and fertilizer, if needed, to get them back on track and flowering.