Q: I had to remove 15 persimmons because of sun damage. One thing I have noticed is that some of the new growth from the main branches is aimed downward, so I am hoping to eventually grow the tree closer to the ground so more fruit is in the shade. All the fruit is small. Hopefully, since this is the first crop, the situation will improve as the tree gets bigger.
A: You’re right, persimmon fruit does get a bit larger as the tree gets bigger, if it is thinned appropriately, and fertilized in spring.
It may be a bit late for your trees, but try planting persimmon fruit trees on the east side of your home so they get afternoon shade. Hopefully, that will reduce the amount of fruit with sun damage. Tree fruit needs only about six to eight hours of full sunlight. Morning sun is best for persimmon trees. If fruit trees are planted too close together, they may get too much shade.
Try growing the Giant Fuyu variety if you want larger fruit when the tree is 3 to 5 years old.
If the persimmon tree is already planted in full sun, I have had luck producing fruit without sunburn with appropriate pruning. The pruning I give them produces the shade the fruit needs to produce undamaged fruit. Before it flowers, but after new growth has begun, I will tip prune them. This means I will prune the new growth by about half as it is developing.
About one month after pruning, new stems produce fruit on the top and bottom of this new growth. When I am thinning the flowers, I remove the top flowers in the hot sun. This gives the bottom fruit the shade it needs.
Unlike most temperate fruit trees, persimmon produces wood in the spring, then flowers on this wood, and finally fruit is produced from the flowers. Never thin the flowers, as you don’t know if they will become fruit or not. Wait until you see small fruit developing, about one-half inch in diameter, then thin.
Another fruit tree that produces its fruit late (on current season wood) is pomegranate. The fruit gets damaged (discolored rind or worse) in full sun, and both the tree and the fruit benefit from afternoon shade when grown in the desert.
Q: What is the proper care for canna lilies. Since they are a dominant plant in my landscaping here in Palm Springs, I’d like to know what to fertilize them with, when to fertilize, when to cut back, when to water, how much and in which season, etc.
A: I like canna lily as well. There are many types to pick from: different heights, flower color, leaf color, leaf variegation. One thing is for sure: These plants love lots of organics in the soil and plenty of water. They even grow in fish ponds.
Plant them in high-water use areas of the landscape with other plants that like lots of water. They can take full sun as long as they get plenty of water and great soil but prefer the cooler sides of the house. Make sure their soil is amended with lots of compost at planting time. They love the surface of the soil covered with wood chip mulch, not rock mulch.
If they are growing well and robustly, they need to be dug up and divided every three to four years. Do this at the same time as you would iris — when it cools off in the fall or very early spring. Fall is best. Divide them, then wait a few days to heal and replant them.
Deadheading is important for looks and continual blooming. Fertilize them three or four times during the year with a rose type of fertilizer: very early spring when new growth is pushing, lightly during the summer months at about half rate, late summer when it starts to cool and once more around Halloween.
To help you remember it think of Labor Day, Fourth of July (half rate), Memorial Day and Halloween. To get vibrant cannas, substitute compost instead of fertilizer for the first or last application of the year.
Cut them back to the ground after they freeze in December or just before new growth if they don’t freeze.
Q: I have two new beautiful vitex trees in a sunny area. A small sprinkler was accidentally left on overnight near one a few days ago. Now it looks a little wilted. What can I do?
A: Turn off the water and hope for the best. Usually, one night is OK for the trees if the soil is free to drain. All you can do is let the soil drain as quickly as possible in case the roots are suffocated from too much water.
You can improve the drainage around this tree. One way is to use a posthole digger to make a 3- to 4-inch diameter, cylindrical hole to a depth of 2½ to 3 feet for drainage. Make them under the canopy of the tree about 3 to 4 feet apart and as close to the tree as you can get.
Q: I am from Midwest, have been here 10 years and cannot even get lantana to grow. But I have African sumac trees in the front and back yards. I love them because they are green all year, but very messy. When I blow the yard, can the leaves be used for mulch? If I could use it, I would.
A: African sumac is a messy tree. A lot of people are disgusted by them. The leaves can be used, but it’s best if they are composted rather than used dry.
Try amending the soil when you plant something and don’t water it too often. Mixing the soil with compost (about one-fourth to one-third) when you plant something is important for its long-term health. Amending the soil with compost at the time of planting will give you a bit larger margin for error.
When you try lantana again, dig the hole three times larger in diameter than the container. If possible, use the soil you took from this hole and mix with about 25 percent to 30 percent compost. As you are planting the lantana, make sure it is the same depth in the hole as it was in the container. Make sure the entire hole and the amended soil in the hole are wet during and after planting.
Q: Something is eating the leaves of my young bottle tree, taking rounded circles out of them. I have looked for insects on the leaves, but I don’t see anything. What is eating them and what can I do to eliminate the problem before more damage is done.
A: That is leafcutter bee. You can tell because of the round or nearly round circles cut from the young tender leaves. There’s nothing to be done about it, and nothing should be done about it. Leafcutter bees are not swarmers; they like living alone. These solitary female bees use the leaves for nesting and pack their babies with something to eat and for protection.
Bob Morris is a horticulture expert and professor emeritus of UNLV. Visit his blog at xtremehorticulture.blogspot.com. Send questions to Extremehort@aol.com.