Bob Morris is a horticulture expert and professor emeritus of the University of Nevada, Las Vegas. Visit his blog at xtremehorticulture.blogspot.com.
Q: Eleven of my 50 young pomegranate trees have leaves yellowing and dropping off. I water this area once a week by flooding. I sprayed a weed killer, 2, 4-D, near the pomegranates, but I protected each one with plastic to avoid damaging the trees. Where did I go wrong here? If the weed killer is the problem, is there any way to save them?
Q: Look what my husband did? He cut my saguaro below the seams before consulting with me. I know it looked kind of sick (the tree, not my husband), but he cut it. I am going to cut those chunks all the way down.
Q: You have converted me to the doctrine of using wood chip mulch. Is there any reason why I couldn’t use wood chips in my strawberry bed? My wife used to put strawberries in pots, and they never did well.
Q: I planted three yellow Lady Banks roses on my south wall when I moved here 10 years ago. Two years ago, my neighbor planted a white Lady Banks rose nearby. This year I noticed white roses growing on my yellow Lady Banks rose. I thought these flowers might be from their plant, but I traced it back to the base of my vine. Will my yellow roses eventually all be transformed to white? How do you explain this botanically?
Q: I can never find Cercis occidentalis, western redbud, at local nurseries. Any idea where I can locate it?
This cool, wet spring was perfect for some early insect and disease problems to appear, namely aphids and powdery mildew. Roses and plants in the rose family, like many of our fruit trees, were rapidly hard hit because of cool, wet spring weather. This will get worse.
Q: Is it too late to prune? We have artificial turf around the tree, but the borders are open for applying fertilizer. Is this good, or should we use fertilizer stakes too?
Cool, rainy weather when pear and apple are in bloom is perfect weather for fireblight disease. Fireblight is a very aggressive and dangerous plant disease that shows up as new infections in about May in Asian pear, European pear such as Bartlett and some apples. It can be a major problem on quince too.
Q: If a fruit tree gets infested with borers in the main trunk and seems likely to die, can I cut off the trunk and allow the tree to grow back from this stump?
Tomato plants that were put in the ground early, before this cold spell, didn’t grow much. This is because of cold soils. Cold air temperatures are bad enough, but when warm-season vegetables like tomato plants have “cold feet,” they struggle to put on any new growth, even with warm air temperatures. If they do get larger because of hot caps or Wall O’ Water plant protectors, it’s not because their roots got larger.
Early Saturday morning I saw water that dripped from the ends of hoses lying on the ground. The water had formed icicles at the ends of the hoses, and temperatures were not freezing during the night.
Q: When can I put tomato plants outside in the garden?
Q: This past year we had lots of fruit, but the problem seems to be the same every year; when do you know its ripe? We pick one fruit every couple of days when they are looking good and try it, but they are sour and hard. Then they slowly start wrinkling and falling off at some point.
Q: How well do strawberries grow in our Las Vegas climate? When is the best time to plant and fertilize them? Any other tips?
Q: I have had much success with sugar snap peas, but lately I’ve been planting sugar snap peas and getting snow peas instead. Is it because the seed is old?
