Q. My junipers are starting to die and turn yellow from the top. I water them twice a day; at 7:00am and 7:00 pm for 45:00 minutes. The nursery told me to water them every other day, 4 days a week, for 1 hour.What should I do to save them? Junipers are not desert plants and may not fare very well over time when surrounded by rock mulch A. I saw the pictures you sent. They appear to be sheared as well. Because of dense, internal shading due to their thick canopies, the “leaves” inside the canopy of these plants die and turn brown. It is only the outer perimeter of leaves that stay green. The inside stems aren’t dead but the “leaves” or “needles” attached to them die and turn brown from a lack of light.             When these plants are sheared, the dead, brown needles in the interior are revealed. Some junipers “re-sprout” from these brown, seemingly dead stems but others may not. However, new growth is slow when they “resprout”.             Spider mites can also cause needles to brown and drop off. Don’t assume your plant has spider mites unless you confirm their presence.             I use a white piece of paper and “slap” a brown branches against the white piece of paper several times. This dislodges the spider mites from the needles onto the white piece of paper. By staring at the white piece of paper for 10 or 15 seconds, you can these tiny spider mites crawling around on it. You must look closely because they are the size of the period at the end of this sentence.             Washing plants prone to spider mites once a month with a stiff stream of water removes surface dust from the needles or leaves. Removing the dust and dirt also helps control spider mite populations. Soap and water sprays also work if spider mite outbreaks are light.             Junipers are notorious for dying if the soil is kept too wet. Their roots suffocate easily in wet soils. The first sign of overwatering is browning of the tips of the stems. This can be from soils that don’t drain easily or when these soils are irrigated too often.             Be careful of that. Juniper roots like to be on the dry side between irrigations. I think this is what the nursery was hinting at.             It’s hard to judge how many minutes to give them but each of them should be fine if they receive 5 gallons of water each, distributed under their canopies. This would require at least 2 drip emitters but 3 would be better.

Q. Respectfully, au contraire, Mr. Morris regarding your advice to not water daily. I rescued my beautiful, full-grown pomegranate several years ago from certain death by daily watering, continuing to date. Pomegranate rescued by watering every day A. I realize your comment is not really a question but I want a chance to discuss it here. Yours is an exception. It depends on the soil, its drainage and how much water is applied. Daily watering can work under some circumstances and under these circumstances it might be the right thing to do. However, it can be dangerous to recommend it for plants particularly in our environment.             Pomegranate is a drought tolerant fruit tree compared to most other fruit trees. You can search any posting on irrigation and pomegranate and all posts from knowledgeable growers will say the same. I would hate to tell people who to irrigate pomegranate based upon one person’s success.             It is well known that shallow, frequent irrigation of woody plants, trees, shrubs and fruit trees for instance, cause the roots of plants to grow close to the surface of the soil where there is a good mixture of water and air. When plant roots grow close to the soil surface, they lose their potential tolerance to dry conditions or drought.             If the soil surface is dry, the roots of plants will grow best at depths in the soil where roots find a happy balance between water and air. Allowing the soil surface to dry discourages roots from growing there but encourages them to grow deeper in the soil.             Deep root growth provides a “buffer” during times of “drought stress” when water is not freely available. Deep root growth also provides a more stable plant during high winds or when they have a heavy fruit load.             Sometimes watering this way does not seem to “pan out” but homeowners find that watering daily with shallow irrigations is easier for them. I agree that under rare circumstances, such as very sandy soils, shallow frequent irrigations are needed. But most of landscapes should not be watered this way.

Q. We are considering planting Sissoo or Raywood Ash in our front patio which is covered with pavers. Are root problems a concern for Sissoo? I have concerns about dieback in Raywood ash because of diseases described in Northern California and Europe. Does our climate reduce the chances of disease problems?  A. To me, the choice between Sissoo or Raywood ash is like picking between an apple and an orange; they don’t do the same job in the landscape. People choose Sissoo as a fast-growing personal shade tree while the Raywood ash is not fast-growing and is not much of a personal shade tree.             Sissoo is much more likely to freeze during the winter here than Raywood ash. Because of their mature size, I don’t consider either one of them as good choices for a single-story residence in a desert climate.             I observed a few Sissoo planted at homes in Las Vegas but most of what I know about this tree’s performance after planting is from homeowners in Arizona. The major complaints are its large size, limb breakage in strong winds, heaving of sidewalks and patios by its roots, general litter from leaves and fruit and root suckering throughout the landscape.             Love it or hate it. There seems to be two opinions about this tree; people love it and others hate it. Not much in between. Homeowners who planted it in Las Vegas were surprised by its size and considered removing them after a few years.             Raywood ash is not fast-growing like Sissoo but easily handles our winter temperatures without damage. But the trunk can be damaged by intense summer sunlight. It does not produce root suckers. Raywood ash is more “ornamental” with its beautiful fall color.             Raywood ash is susceptible to a disorder, disease if you want to call it that, called Ash Decline. This disorder has been a problem in Las Vegas since the 1980s beginning with Modesto ash and later with Raywood ash. I generally don’t recommend planting ash trees susceptible to this disorder in the Las Vegas Valley.             Both trees should not be planted in a desert landscape surrounded by rock. You’re asking for trouble if you do. Instead, plant them in lawns or surrounded by other plants that require moderate to high amounts of water.

Q. Your advice has helped me get a couple of dozen figs off my relatively young trees this year.  However, the attached photos show where there were two figs a few days ago and now they are entirely eaten.  I have a net over them so I don’t think it’s birds and I cannot see bugs anywhere on the plant. Figs eaten, possibly rats A. Any animal that is an omnivore will eat figs. Birds usually peck at the fruit and it is obvious the remaining fruit was pecked apart by a bird. Birds get under netting unless it is tightly pinned to the ground. You can visualize where the bird landed on the branch and did its damage.             June beetles are flying now and they will also devour figs. They seem to prefer yellow or white figs. However, the bird netting should keep them out. These insects will be gone in a couple of weeks and your tree will continue to produce fruit. Pomegranate fruit definitely by rat             Other critters, like rats, eat them ripe or unripe and leave exactly what you are seeing; the fruit entirely gone except it’s stem still attached to the tree. Look at where the fruit was eaten and ask yourself the question, “Is the branch strong enough to support the weight of a rat?” If the answer is yes, you know rats are in the area, it looks like a rat ate it then it probably did.             Other possibilities include ground squirrels. They like to steal grapes when they are ripe and can climb trees as easily as rats. Ground squirrels will completely clean out almond trees overnight.

Q. I changed my drippers to adjustable types and have problems with them working in my backyard. I fix them either by adjusting or removing the heads. Now they work fine. This happens throughout the year but I have never seen so many fail at the same time. My front yard also uses adjustables but don’t have the same problems. I was thinking about going back to drippers for reliability.  Variable flow or adjustable drip emitter above and below.Do you like to play Whack a Mole? If you do, then you will love adjustable chip emitters. Close-up of an adjustable or variable drip emitter. I don’t hate them but I don’t like them very much and give precision drip irrigation a bad name. These are precision drip emitters that met or release water at specific volumes over a given time, usually one hour. They are color-coded by the manufacturer to indicate how many liters or gallons per hour they release. The pointed end is pushed through a hole created by a punch specifically meant for drip tubing. Do not use a nail or Phillips screw driver to make these holes. Spend four dollars and buy a punch.I call these types of emitters “precision drip emitters” to differentiate them from variable drip emitters which are extremely imprecise in their delivery of water. This is a flag-type precision drip emitter called so because of the triangular flag. The flag has a stem attached and can be removed from emitter for easy cleaning. I like them because they are so simple to use, inexpensive and easy to clean if they get plugged. A. I call “dippers”, “drip emitters” or “emitters” but I think we are talking about the same thing. I work with drip irrigation all over the world. The major reason drip systems fail is because the system is not cleaned and “flushed” regularly. Flushing and cleaning drip systems must be part of a regular maintenance schedule.             When cleaning and flushing a drip system, the primary filter or screen must be cleaned Screen filter called a “Y-filter” because it’s at an angle like the letter “Y”.This black housing can be twisted open and inside there will be a screen filter which should be washed and flushed to remove sediment and debris. There is a round On the top which can be opened for flushing the inside of the screen but it does not remove everything. thoroughly, every “dead end” must be opened and flushed with several gallons of water and emitters should be inspected for plugging when they are operating. If emitters are plugged, they must be cleaned or replaced if they cannot be cleaned. The ends of polyethylene tubing or drip tubing can be bent over and this double ring device can be slipped over the end. This double ring keeps the tubing bent over to stop water flow but also allows the end of the tubing to be opened quickly and flushed to remove debris and sediment.Some people have used electrical tape to do the same thing but these are inexpensive and fast. This is auto flush for drip irrigation. The double ring above must be open manually. This can be inserted inside the drip tubing and flushes the polyethylene pipe every time the valve comes on. I would still recommend flushing the lines manually periodically and after repairs but this helps reduce some of the labor.             A major problem is created when drip systems are repaired and but not flushed afterwards to remove dirt that enters the drip lines. If drip irrigation lines are cut and repaired, I guarantee dirt entered these drip lines. It is mandatory that the “dead ends” associated with the repair are flushed immediately afterwards.             Drip system filters are cleaned and the system flushed because dirt or sediment in the water collects inside the filters and eventually plug drip emitters. Flushing the irrigation lines removes algae and bacteria that plug emitters as well.             How frequently to clean and flush a drip system depends on the quality of the water and how much water flows through the system. Irrigation systems should be flushed more often in summer than winter.             How long it takes to flush and clean depends on the design of the system. Poorly designed drip systems take longer to flush and clean. When designing drip irrigation systems, minimize the number of “dead ends” so that flushing the system takes less time and there are fewer places that accumulate “dirt” and slime.             Most drip irrigation systems attached to municipal water are flushed once a month if the municipal water delivered is clean. Sometimes it is, sometimes it isn’t, depending on the age of the municipal system.             Even though filters must be installed as part of every drip system, small amounts of sediment pass through these filters and eventually become a problem if the system is not flushed and cleaned regularly. Failure of drip systems is gradual, not like an “on and off” switch.             Drip systems attached to well water should be flushed more often because this water is “dirtier”. How often depends on the quality of the well water which varies from well to well. Typical cleaning and flushing might vary from weekly to biweekly during the summer months.             Algae and bacteria (you might call it “slime”) grow inside every irrigation system. Algae and bacteria are not problems with most sprinkler systems but can be problems with drip emitters because the “emitter” holes are so small.             In my opinion, drip irrigation systems must be flushed and filters cleaned on a regular basis depending on the quality of the water and the gallons used. The drip emitters used should be easy to clean and inexpensive. Variable drip emitters are inaccurate in their delivery of water but are subject to the same plugging as all other drip emitters.

Q. Why does your list of recommended fruit trees have no citrus? I understand the problem with freezing during the winter but nurseries and garden centers here sell citrus. If I could provide some sort of wind block from cold winter winds and some frost protection, would lemons or oranges have a chance or are they just generally doomed?  A. Generally, I do not recommend growing citrus in the Las Vegas Valley. Is citrus grown here? Yes, it is growing successfully in many backyards. So why don’t I recommend growing citrus? Because many planted in our Valley die during freezing winter temperatures. Some don’t.             Successfully growing citrus is better than a crapshoot. The overall climate of the Las Vegas Valley is too cold during the winter to recommend citrus. However, there are protected nooks and crannies in people’s backyards that allow for citrus to be grown. These protected nooks and crannies are called microclimates.             The major limitation for citrus here is cold winter temperatures. Cold winter temperatures are made more lethal when accompanied by strong winds. Remove these two obstacles and citrus does well.             After an ideal microclimate is found, citrus must be healthy to survive our extremes of heat and cold. Amend the soil with compost at planting time. Do not apply citrus fertilizers after August 1. For long-term health of the tree, avoid surrounding it with rock and desert landscaping.             And finally, choose fruit that you want combined with tolerance to freezing temperatures in your microclimate. Tolerance to winter temperatures is best with kumquat followed by mandarin orange, Myers lemon (only Myers) and grapefruit. Least tolerant to cold are the limes, true lemons like Ponderosa or Eureka and some of the specialty oranges.             Planting citrus here is not for everyone. Proceed with caution and look at it as a fun experiment in gardening.

Q. I have a 5-year-old orange tree and this year it has produced quite a bit of fruit. Many hang at the very end of branches and some are in clusters. I’ve read somewhere to prune these fruits However, I am not sure when to do that.  Do I prune them now? A. Removing the fruit so that other fruit can become larger is a type of pruning called “thinning”. It is also done if the amount of fruit could break limbs or cause other fruit to be pushed off the tree.             Thinning or removal of fruit from the limbs of fruit trees with a focus on increasing the size of the remaining fruit is done when the fruit is still very small. Usually about the size of your thumbnail. If the fruit becomes large before it is thinned not much benefit will be passed on to the remaining fruit.             Some fruit trees are not thinned because removing fruit doesn’t seem to make much difference and increasing the size of the remaining fruit. This is the case with most nut trees, figs, pomegranates and citrus.             Most citrus is not thinned so the remaining fruit becomes large. However, if the weight of this fruit threatens breakage of the limbs, then, of course fruit is removed to eliminate that possibility. It is best to remove the fruit early but if that is not done, remove the fruit as soon as you see the threat of limb breakage.Otherwise, support the limbs so they don’t break and do some light pruning after harvest.

Q. I have several really tall thick pittosporum plants – some well over 7 feet tall and usually thick with foliage, but this year they seem to have suffered a LOT from the heat.  I checked at the base and the most damaged one — down to a mere skeleton — is getting water.  They are about 20 years old — is there an “age limit” to plants like these? Thats a good looking full-sized Pittosporum with good leaf color. Obviously healthy. Are they THAT heat sensitive?  I’d hate to lose them all.  When, and how severely, should I prune?  Take the more damaged ones back down to sticks and hope for recovery? Drought on Pittosporum due to high temperatures and wind. A. That is what a full-sized Pittosporum is supposed to look like. I like the color in the form of the undamaged plant.  The damage top and suckering from the base tells me the plant is putting on some new growth where it is easiest for it. When everything is optimum, the plant will always try to get larger and put new growth as high as it can. When conditions are not optimum, then it will try to put on growth in places where it spends the least amount of energy and trouble.  Sprouting occurred due to the cuts made on the stems and the stem exposure to sunlight combined with…thats an easy place for the plant to put on new growth. You remove something and it will try to regrow in that spot to get that energy from the sun. The damage at the top in the suckering at the base tell me the plant is not getting enough water when it is watered. Plus it was opened up with some pruning cuts at the base. I would add 2 or 3 more drip emitters to the base of that plant and try to cover at least half of the ground under its canopy with water. This means spread the drip emitters out about 12 to 18 inches apart under its spread.  I would also put about one bag of compost under the large plants and water it in with the hose. Keep the area wet for the following 1 to 2 weeks. I think you will see a change in 2 to 3 weeks. Prune out the dead branches by cutting at a Y or joint between the dead branch and a living branch deep inside the canopy, 8 to 10 inches inside of it.

Q. A combination of overwatering and this heat caused my 9-year-old dwarf pomegranate leaves to yellow and drop on about 1/3 of the plant.  I turned off the water and hand watering it with small amounts of water. The only thing I did differently was give the plants a small dose of MiracleGro in the spring. Any suggestions?  This pomegranate does not look all that healthy. The leaves should be much darker green. Probably watering too often caused it and the dieback. Use more water and apply it less often. Let those roots breathe! A. This is not your common ordinary disease problem. It is humanitis! And the fertilizer did not cause it either. Pomegranate is remarkably resilient in our climate if it’s not watered too often. Avoid watering these plants daily. Give it plenty of water when you irrigate and then hold off until the next irrigation. I water newly planted trees this spring every other day when temperatures are above 110° F. Here’s a pomegranate yellowing. Why? Because it was planted in a lawn that needs watering every day. Watering once a week is enough in early spring and late fall. As it gets warmer, water more often. You should never have to water more than once every other day in the hottest weather!             Leaf yellowing and drop can be a temporary problem with many fruit trees regarding water issues. Give the plant some time to respond if these branches are still supple and bend easily.              If these branches have dried and appeared dead, cut them off just above healthy growth. I have removed damaged parts during the summer months and the plant re-grew without problems.             Use wood chip mulch on the soil surface to help preserve soil moisture during the heat. This gives me one extra day between waterings. I am giving new plants about 5 gallons, 3-year-old trees about 10 gallons, 5-year-old trees about 15 gallons and trees over 8 years old from 20 to 30 gallons depending on their size. A dwarf, 9-year-old tree is going to be in the range of 10 to 15 gallons each time you water.             I have had no problems with loss of leaves during the summer but some of the 20+ varieties I have grown had winter cold damage. Some varieties of pomegranates, particularly those with Russian names, showed some winter cold damage. Older, common varieties sold for many years in the American market sailed through cold winters down to 10° F.

Q. My fiddleleaf fig houseplant has brown spots on some of the leaves. I’m watering it every other week. I have looked but can’t find the cause of these brown leaf spots. I thought it might be a fungal issue, so I applied liquid copper but that didn’t make any difference. Do you have any idea what causes these spots and what I can do to help this houseplant? I really appreciate it when I am sent so many pictures. This helps a lot in diagnosing the problem.Fiddleleaf fig, Ficus lyrata A. Fiddle leaf fig has made a comeback. It used to be very popular 40 to 50 years ago. Now it’s on the rebound for interior designers as a houseplant.             Fiddle leaf fig in the wild starts its life as an epiphyte, similar to orchids. Eventually they root into tropical soils and live their life as a small understory tree, strangling the mother tree. Which means it likes filtered and indirect light. It can tolerate periods of time without soil moisture as well.             Brown spots on leaves can be a disease problem, particularly if they are closely associated with leaf veins. Plant diseases on houseplants are not common in desert environments because of our low interior humidity.              Insects feeding on these plants are a bigger problem. Inspect the plant for spider mites, scale insects, mealy bugs and fungus gnats living in the soil which can cause problems similar to diseases.             Plant diseases are closely associated with the health of the plant. To improve its health, and ability to ward off diseases, make sure it gets adequate light, water and fertilizer. If you need to stake this plant so it stands upright in a container, it is a good indicator it has not been getting enough light in the past.             Lack of light is a common problem for houseplants because of our dark interiors. Larger houseplants slowly decline, beginning around 6 months after they are plunged into dark interiors. Smaller plants decline more quickly. If they are large plants, they have enough stored food to live for several months before they decline.             This plant requires placement near a bright window but not in direct sunlight. Once a month turn the plant so that different sides of the plant receive light.             When temperatures are pleasant outside, place this tree in a sheltered area on the north or east side of the home under a tree. During this time, it can start building up its food reserves for that long, dark haul inside the home during summer months. Never place it in direct sunlight which damages the leaves and causes them to drop.            Lift the container. It is dangerous to water on a schedule unless you are confident this schedule fits the needs of the plant. Watering of this plant can be withheld until the soil is quite dry. Instead, lift or tip the container to judge its water content. Water is heavy. Potting soil containing water is much heavier than dry soil.             Use a pencil. Sticking the pointed end of a pencil in the potting soil can help judge the moisture content. Pencils slide into moist soil much easier than dry soils.             User soil moisture meter. They cost about 10 bucks at any nursery or garden center. They are good for judging relative amounts of water but not exact amounts of water. This moisture meter will tell you if the soil is dry enough to water or if it’s still wet and should not be watered.             Avoid using straight tap water. Our tap water has lots of salts in it. Instead, use distilled or reverse osmosis water and blended with tap water 1:1 or more dilute. Give it enough water so that one 4th of the applied water comes out the bottom. This helps remove salts.             Add fertilizer based on the growth of the plant. If the plant is growing rapidly, temperatures are warm and there’s lots of light, water and fertilize more often. Add a small amount of fertilizer to the irrigation water at every 3rd or 4th watering.             Interior plants should be repotted every 3 to 4 years. This means gently lifting the plant from its container and shaving off a 1 to 2 inch layer of soil from the root ball on all sides. Use a sharp, sanitized knife. Disinfect the container and repot the plant using new potting soil.