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Prune fruit trees any time after leaf drop

Q: When can I prune my pomegranate tree? How hard or heavy can I prune it? What about my fig tree? Both have shed all their leaves.

A: Prune pomegranates or any of the fruit trees any time after leaf drop. If you are not an experienced pruner. Do all the pruning after the leaves have dropped before new growth in the spring.

You can remove a lot of wood from pomegranate since the remaining wood doesn’t seem to sunburn as easily as other fruit trees. The fruit, however, does sunburn resulting in an inferior visual quality because of the darkened rind facing the sun but doesn’t affect the arils inside.

Commercially speaking, there are three visual factors that result in lower quality fruit: size, sunburn and blemishes on the rind such as scratches. Because of the intense sunlight in the desert, fruit produced toward the interior of the tree, shaded by tree growth, produces higher-quality fruit.

Pomegranates are typically pruned as a shrub with a maximum of five stems coming from the ground. All the other growth, suckers growing from the ground, are removed. Sometimes pomegranates are pruned with a single trunk or just two or three trunks coming from the ground. It’s your choice.

But allowing a maximum of five stems is easier to manage and produces larger sized fruit, but a smaller number. The total weight of the fruit removed from the tree is about the same, but there are fewer total number of fruits. Larger fruit is considered more desirable.

If you are an experienced pruner, use a lopper and saw to remove large branches only during the winter months after leaf drop. But use hand shears anytime during the year and when you see a problem developing. Just be careful of removing too much with hand shears since we want shading of the limbs

The amount of wood removed after the tree is mature depends on how large you allow the tree to become. The size of the tree that you allow depends on how much room it has available to grow and how close it is planted to other objects. Bad pruning practices and planting trees too close to each other will result in most of the fruit produced at the top of the tree.

I have persimmon and pomegranate pruning classes scheduled for January at the Ahern Orchard downtown, off of West Bonanza Boulevard. Sign up for these classes, if you need them, on Eventbrite or contact me.

Q: What is safe to transplant now? I mean, there is something from the nursery that I’d like to plant in the ground.

A: You can plant in our climate probably about eight months of the year. Arguably, you could plant during any month. It’s just that there are preferred times to plant here, when plants perform better after planting, and it’s not so rough on them.

In northern climates, the ground freezes for several months and nothing is planted at that time. Here it’s different.

The months that I would avoid planting are during the summer months when it’s hot. The exception, of course, are cacti and most succulents. The ideal times to plant all plants are in the spring and late January through about early May. If you want to split hairs, the fall months also are perfect to plant.

The problem during fall months is plant availability. It’s a “chicken and egg” kind of a situation. The nursery industry is geared up to produce plants in the spring and that’s when people traditionally think about it. However, if you do shop around in the fall, there are plants available.

The fall months of mid-September through October are ideal times for most plants because you essentially get two “springs” (fall and the following spring) for root growth and establishment. The only exception I would make are palm trees, which are best planted in the spring or even during the summer months.

If you read my advice closely in the past, you know I’m going to tout the benefits of good compost as a soil amendment when planting. The other two important factors are the size of the hole and staking the plant to keep the roots from moving after planting.

Most of you know I strongly support the use of woodchips applied to the surface of the soil after planting to continuously improve the soil and keep it from entering the landfills.

However, I suggest you don’t use it until the soil begins to warm in the spring. Woodchips help keep the soil cool by shading it from the sun. If you do plant now, apply woodchips in the spring as the soils are starting to warm. This keeps the soil temperature in the range for best root growth and plant establishment.

Q: I have four 10-year-old oleanders along my lot line. Last year they developed a fungal disease on two of the plants that resulted in weird-looking leaves and stems that were stunted and yellow. I cut them way back and used a product on the cut areas the nursery said would kill the plant. They came back better than ever but still have the same growths.

A: From your picture, it does look like witches broom, which is a fungal disease. It can easily spread from plant to plant. Removal of the plants is the only known cure for it. I mentioned it on my blog in 2014 when someone else asked about it after seeing this type of weird growth on oleander.

It was reported in Florida in the 1930s and 1940s, and experts recommended removing the plant as fungicides didn’t seem to help. It is still worth trying to prune them and see what happens this spring.

Try pruning these plants within 6 inches of the ground this winter and let them regrow. Since pruning didn’t work in the past, try disinfecting pruning equipment between each cut to avoid spreading the disease from cut to cut and reinfection.

You can use 70 percent alcohol and wipe or spray them on the blades between each cut. You can also disinfect the blades by heating them with a lighter. You can also use bleach. but make sure that you apply oil to the blades after the job is done. This may be overkill but it’s worth a shot.

Let the plant regrow from these extensive pruning cuts and see if this gets rid of the disease. If it doesn’t, have the plants removed and dispose of them. This time recut the stems close to the ground so there are fresh wounds.

Apply a brush killer that contains the active ingredient dicamba or triclopyr to the fresh cuts. Apply it in a spray bottle or use a paintbrush. Apply to fresh wounds because that is more likely to kill the plant.

Have a professional remove the roots. With the right equipment, it’s possible to remove them without damaging the driveway. You should be able to plant again in the same hole.

Q: Is it OK to trim the dead frond from Mexican fan palm trees this time of the year? My association sent a letter to trim dead fronds.

A: Remove palm fronds anytime to make it look better but just don’t remove too many. The remaining fronds should occupy an upside down half circle. The remaining fronds help protect the bud from winter damage due to winds and sunburn. Excessive removal of fronds can weaken the tree.

There is no problem removing fronds now if you follow this precaution. However, it’s preferred to prune them in late spring or early summer after they begin flowering since you can remove fronds and the flower stalks at the same time. This helps prevents seeds from scattering everywhere in the landscape.

Bob Morris is a horticulture expert and professor emeritus of the University of Nevada, Las Vegas. Visit his blog at xtremehorticulture.blogspot.com. Send questions to Extremehort@aol.com.

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