The University of Nevada Cooperative Extension’s desert landscape design classes, "Landscape Design with the Desert in Mind," will run for eight weeks starting the evenings of Sept. 14 and 15. During this series of classes that I assembled, you’ll learn to design your own landscapes and how to install them. For more information, please call our master gardener help line at 257-5555.
Q: I have a white peach tree that each year I take off peaches so they aren’t too close together. I read that allows the remaining to grow larger. I end up throwing away 50-75 every year. Is this correct? It seems like such a waste.
A: It sounds like you are trying to do what we call thinning. But you may be doing your thinning too late.
We want to thin or remove fruit from the tree when the fruit are still very small and immature. This gives the remaining fruit more nutrients and they will get larger since these nutrients are no longer divided up between so many different fruit. If you wait too long to remove fruit, thinning will not work as well or perhaps not at all.
On peaches, fruit should be thinned when they are about the size of a quarter, sometime in March. The remaining fruit are usually spaced about 4 to 6 inches apart depending on the size of the fruit we want to obtain and the vigor of the tree. With very vigorous trees we remove less fruit, while on less vigorous trees we remove more fruit.
If you are in an area that seldom freezes after Feb. 1 then you could actually thin at the time of flowering; we do not do this at the University of Nevada Cooperative Extension Master Gardener Orchard in North Las Vegas in case we have a late freeze and lose the remaining fruit after we have thinned.
Q: This year my peach tree is getting attacked by birds who keep eating the peaches. What can I do to stop them from eating my peaches?
A: If birds are problem, I usually like to pick peaches a bit early and let them continue to ripen at room temperature off of the tree. Birds tend to damage fruit when they are ripe, not usually before that unless they are very hungry and have nothing else to eat. On occasion they will sample unripe fruit but this is not the rule.
If birds are problem, I watch for the first signs of damage and then begin to harvest the fruit as more get to that stage of ripeness. Harvesting a tree usually runs about seven to 14 days, depending on the weather.
Q: What is the best way to wash peaches since many have bird waste on them. Are they OK to eat once washed?
A: As far as washing goes, just rinse them with clean water and peel the area of the fruit where there are problems if you are still bothered by them. Normally rinsing is enough.
Q: We have a California pepper tree that was planted from a 24-inch container about two years ago. The tree is well-watered and deep root fertilized twice a year. Last December, the tree was bent in the crown by the 8-inch snowfall that we experienced. I added bracing to counteract the bend. About two weeks ago the high winds snapped the stake restricting the bend. I was surprised to see the trunk bend about 6 inches above the ground like a wilted carrot. The crown of the tree was holding the trunk off the ground. The tree did not uproot. The trunk did not fracture. I righted and restaked the tree. Is this tree a lost cause? I cannot see maintaining the stakes forever.
A: First of all, fertilizing a landscape tree more than once a year is probably unnecessary and may actually contribute to its weakness due to rapid, succulent growth. In fact, if your tree is growing well, you might consider skipping a year unless you are having some micronutrient problems such as yellowing from iron chlorosis.
But this is not your question. Once you begin to stake a tree for reasons other than getting it established in the first growing season or getting it to re-establish after some damage it may never be able to support itself.
It sounds as if there is a lot of internal damage to the tree in its trunk. My guess is that the trunk itself lost its support from the central cylinder of vascular tissue and the wood in its interior was damaged.
The tree’s central core of support is the vascular system that is just inside the bark. To the inside of the vascular system is wood that is dead, which resulted from the previous years of vascular systems. This dead wood on the inside provides little support to the tree. It’s real support comes from that cylinder of living tissue just under the bark.
Leave it staked for one to two growing seasons and give the tree a chance for the developing new vascular system to develop and re-establish support for the trunk. It would be important to see if you can immobilize the trunk as much as possible.
I really think the tree is lost and should be removed, but it is worth a shot to see if it can heal. You have an interesting problem. Let me know how it turns out.
Q: Last fall, I completed a front yard conversion and it turned out fairly well. I managed to cut my water usage down from 10,000 to 1,000 or 2,000 gallons per month. I planted two flowering plum trees. They bloomed nicely in March and one of them put out a nice healthy sprout from the base of the trunk, 1 inch below the dirt. For the fun of it, I let it grow and now I have a tree that is about 5 feet tall with a trunk about half the diameter of the main tree. The leaves are green and not purple and the branches are light brown and not like the main branches. Do I have another plum tree growing and should I let it grow? Will it stunt the growth of the main tree? Right now it looks better than the main tree.
A: First of all, purple leaf plum may have some problems in your landscape if the ground is covered with rock mulch. This tree can handle a fair amount of heat but if it is planted in the hottest part of the yard it may begin to scorch and die back early in its life.
My guess would be that over time you may see some sap oozing from the branches due to heat stress if it has a south- or west-facing exposure. The tree also may begin to show signs of yellowing in three to four years due to the rock mulch. This tree is not a terribly good choice for the dry part of a desert landscape, if that is what you created.
Purple leaf plum is actually two trees in one. The purple leaf plum is grafted or budded on to a tree that is used as its rootstock. The tree used for a rootstock is usually also a plum tree but it has green leaves. If growth from the rootstock occurs and is allowed to develop you will have two trees arising from the same trunk. Higher on the trunk will be the purple leaf plum while lower on the trunk, arising from the rootstock, will be a second plum tree but this tree will have green leaves.
You would have a novelty if you left both trees growing from the same trunk, but I will warn you that the tree developing from the rootstock, the green one, is typically more vigorous than the purple one. Eventually the green portion of the tree will outperform and dominate the purple side of the tree. In fact over time it may suppress it enough that the purple side may die.
Bob Morris is an associate professor with the University of Nevada Cooperative Extension. Direct gardening questions to the master gardener hot line at 257-5555 or contact Morris by e-mail at firstname.lastname@example.org.