Q. I have a single, four year old pomegranate tree in Las Vegas.  The tree produced excellent fruit the first three years.  This year the fruit was spoiled as they came off the tree.  The tree appeared normal.  Looking at the fruit, it wasn’t evident if it was infested with a bug or a disease.  Would you have any suggestions on what caused it?  Adults A. The most likely reason would be an insect called the leaf footed plant bug. They will infest pomegranates, almonds and pistachios most frequently. Their feeding can cause small holes in the outside of the fruit or nut.             This wound can open the fruit for infection by disease and possibly cause a nut not to develop inside the shell causing what we called blanks, or no nut, to develop. You will see these insects overwintering on your fruit trees or nearby landscape trees as well. Adults and nymphs             These are nefarious denizens of the worst kind and seem to have no value except to breed more of the same. I would recommend spraying your fruit and nut trees with dormant oil twice during the winter and follow this a few days later with an insecticidal soap.             I have seen most of these adults overwintering on the stems and trunks of trees, usually in the sunlight because of the heat they can get. I hope this helps.

Q. I have a large pot of sage growing on the protected side of my house (north) where all my citrus and other herbs have done well.  I notice that when the weather cools, the sage leaves turn a whitish color.  I collected some for sage dressing, but I didn’t bother using the white leaves, just the green ones.  Is this a natural occurrence during cold weather?  Would those leaves have been okay to use?              I dry the good leaves in the oven at 225 degrees for about 1 hour, leave them out in the house to get thoroughly dry for a day or so, then crush them in a coffee grinder.  Works great for my use in the kitchen, especially for sage dressing.   A. This white discoloration is probably some damage to the leaves due to cold. You are right, don’t use them.             However, drying at 225F is far too high. This should be done at temperatures between 95 and about 125F. There is a lot of damage done to the herbs at high temperatures, particularly above 140F.             Our weather and climate is perfect for drying herbs without the use of extra heat. It will take longer than one hour but the quality will be much, much better. Cut the stems of those with flower buds just starting to form. Hang these bunches in the open air and not in intense sunlight for 1 week to dry.             If this is too slow for you, use a cookie sheet and put in the oven at the lowest temperature that provides heat. Bottom line, do not use excessive heat and keep them out of intense sunlight while drying. Hope this helps.

Q. I’ve enjoyed your articles in the LVRJ over the years. I Love my backyard garden here on Sunrise Mountain but it’s been a challenge compared to growing a garden on the Island of Maui.  I would like to augment my garden soil with the wood ashes from my fireplace. Would that be good for the garden soil?  A. If these ashes are from plants then there should be no problem incorporating some of it. Much of this has to do with the volume that you want to add. Small volumes of this distributed over a larger area will be no problem as it will be high in some nutrients. One ton of wood ash has about 15 lbs of phosphorus and 50 lbs of potassium but it is strongly alkaline which we don’t need. If this ash is coming from plastics or other manufactured products then I would not use it.

Sour orange rootstock that took over a Navel Orange tree Q. I have a dwarf tangerine in a container that gives lots of fruit but it is sour. Why? A. Sugar content is developed over time as fruit matures. When the fruit is immature it usually has higher acidity and low sugar content. As the fruit matures the acidity drops, and sugar content climbs. Be sure to wait for full color development in the fruit and it should be at its highest sugar content.             Tangerine is sometimes grafted onto sour orange rootstock. If the tangerine part of the plant dies, the sour orange rootstock will replace it producing beautiful fruit but very sour and it will never become sweet. If this is the case, and this happens a lot in Las Vegas due to our winter freezes, dig it out and replace it.

Q. I now water once a week but my shrubs are looking like they might in the hottest part of the summer. Leaves look dry, burnt and falling off. My average shrub is about 3’x3′ and receives 3-4 gallons per week week based on my emitters and time on. Did I cut back to much ? What should I do to try to revive them ? A. Your watering sounds very appropriate and probably what I would have scheduled as well. You have to make sure, however, that the water which is scheduled to be delivered to your plants is actually getting there. Make sure you check for plugged emitters when the system is on. You should have a filter on your drip system even if you are on city water.              It could be several possibilities. I have to walk through them with you because I don’t know much about their previous history. For me, it looks like possibly watering, possibly collar rot at the base of the trunk where the rock mulch sits against the stem, it could be very low temperature damage as possibilities. If there were some very low temperatures just prior to that than this could be just that. If there were no low temperatures than most likely it is not. Then we have to look at watering issues including the rock against the trunk. First determine whether the plant is dead or not. Bend some branches and see if they snap. If they are still supple and just have damaged leaves then it is a temporary setback and they will regrow and set new leaves in the spring. If they snap when you bend them, it may be dead. You will have to pull it anyway so start bending the branches and see how much of the plant is dead. If the amount is sizable, remove it. When you remove it look at the trunk where the rock mulch was resting against it. Use a knife or your thumbnail and scrape the bark away from the trunk starting about an inch above where the rock mulch sat and down along the stem to the roots. Look to see if there appears to be a dark area or rotten area in the trunk or bark around the rock mulch line. If there is, then it is collar rot. Make sure on any new shrubs that rock mulch does not lay against the trunk or, in some cases, the plant was not planted too deeply. It should have been planted the same depth as it was growing in the nursery container. Nurseries don’t have many plants this time of year because they are trying to reduce their inventories. You can look for a replacement plant but chances are you may not find one that you like until next spring when it gets warm. I hope this helps.

Q. How do I get my Christmas cactus to bloom? I was given a 9″ pot back in November, kept it indoors with plenty of light, only to find out that it’s supposed to be in the dark for 14 hours a day. I started that 3 weeks ago, been watering once a week, gave it cacti food twice, but no blooms. A. The Christmas cactus is a true cactus and nearly identical to the Thanksgiving cactus. These cacti have slightly different bloom times so they get the names Christmas and Thanksgiving cactus because of their bloom times.             The amount of light (actually it’s amount of darkness) will typically get them to bloom if all the light they receive is natural daylight. It’s when they receive extra light inside the home that it can break this rhythm of flowering and cause them not to flower at this time of year.             These cacti bloom when the nighttime darkness approaches what we get a minimum of 12 hours of darkness. So if they are growing inside they need to be covered so they receive no light from artificial sources. Once covered they will bloom if they remain covered, religiously, for six weeks . They also respond to cool temperatures. So placing them in a colder location in the dark also will help them to bloom.             Christmas cactus is what we call an epiphytic cactus which means it does not grow in the soil in the wild but on the surface of other plants such as trees. We can however put them in containers and grow them in containers with soils amended with lots of truce one compost, similar to what they would find growing on the surface of a limb in the tropics. This is much like orchids and bromeliads. These cacti can be grown outside here on the northern or eastern exposure in a well amended soil or in containers but you must bring them in if there is any chance of freezing temperatures.

Plant lettuce, peas, cabbage (transplants), cauliflower (transplants), carrots, radishes and spinach. These vegetables can germinate and handle lower soil temperatures in the warmer parts of the garden (45F soil temperatures for germination). Prepare the soil by loosening it and applying a starter fertilizer high in phosphorus. Cover the seeds with a dark topdressing to help warm the soil. Activated carbon works great for transferring heat to the soil.

Lowering the height of fruit trees Pruning: lower the heights of fruit trees. Lower the heights of fruit trees if you want to do most of your tree management without a ladder. Lowering the height of your fruit tree to a pruned height of 6 1/2 feet will allow you to prune, spray and harvest while standing on the ground. Most full sized fruit trees can be kept to this height through judicious pruning methods. Apples should be grown on a semi-dwarfing rootstock.  Pruning: begin pruning for production. Each type of fruit tree is pruned differently. You must know where your fruit is being produced on the tree that you are pruning. 4 to 8 inches of mulch on the orchard floor Mulch. Use organic mulch in the Orchard or around fruit trees. This is not the same as bark mulch which is inferior to wood mulch. Wood mulch can be kept to a depth of 4 to 8 inches around fruit trees. On younger trees, keep wood mulch 12 inches away from the trunks until they are 6 to 8 years old. Green waste from pruned and chipped ornamental trees makes an excellent mulch. Avoid using trees such as Mesquite with their large thorns and palm trees which decompose very slowly. Organic mulches such as wood mulch return nutrients to the soil, increase microbial activity, retain moisture around the plant roots, reduce weed problems and help keep the soil cool. Fruit trees at Orchard irrigated by modified flooding: bubbler and basin Asparagus turning brown in the winter Irrigate fruit trees deeply every 10 days. After leaf drop, irrigations can be applied every 10 days to two weeks if you have a surface mulch applied to the soil. Sandy soils may require irrigations weekly to every 10 days. Heavier soils may require an irrigation every two weeks. Applying compost to the raised beds Cut down asparagus. Asparagus growth is cut to the soil surface when it turns yellow or brown. If this does not happen by the end of the month, cut the asparagus down to the soil surface. Compost planting beds to be rototilled. Those beds which have not been planted should be prepped for next season. Use a high grade of compost to improve the soil to a depth of 12 inches. Incorporate a high phosphorus fertilizer in the planting row or in the backfill when planting transplants. Borer control. This time of year concentrate on removing borer damage from fruit trees. Look for borer damage on the upper surfaces of limbs, particularly of peach, nectarine and an apricot. Using a sharp, sterilized knife remove the damaged wood from these areas. Be sure to cut all the way down to fresh wood when removing damaged wood. Let the tree heal by itself. Do not apply pruning paint but you could apply whitewash. Whitewash applied to fruit trees Dormant oil application. Dormant oil is an insecticide made from petroleum products used in organic production. The oil itself is not toxic but spraying it on the limbs and trunk of fruit trees helps to suffocate overwintering, usually soft bodied, insects that are pests of tree fruits. Usually to applications are made during the winter months. Weed control. Weeds that are living close to your fruit trees provide homes for overwintering insects. Once your trees begin growing in the spring, these insects move from weeds to your trees. Keep in areas near your fruit trees without weeds. Borere control with a sharp knife Renew whitewash on fruit trees if needed. Whitewash provides a light colored covering to the outside of the bark of the tree and its limbs. It is particularly important in reducing sun damage to fruit trees due to our high light intensities. Whitewash can be made by diluting white latex paint with an equal amount of water or more. Dilute the white latex paint so that it will color exposed areas of the tree white and reduce sunburn. Reducing the sunburn will reduce the damage from borers. Pull wood mulch away from the trunks of young trees about a foot. Wood mulch that gathers around the trunks of small trees can damage them. Limb spreaders on a young apple tree Remove any stakes from trees planted early in the year. Fruit trees that are planted correctly and are not overgrown in their containers will need staking for only one season. If your trees have not become established after one season, there is a problem. Remove limb spreaders that were used earlier in the year. Limbs spreaders are used to increase a limbs angle of attachment to the trunk of the tree. Ideally, this should be a 45° angle. Limbs spreaders can be applied to the tree now but there is less danger of breakage in larger limbs when the sap is flowing in March. Ideally they should be applied when the limbs are one to two years old.