Dormant oil sprays are applied on warm, windless days during the winter to trees and shrubs after they are pruned. That’s when insects susceptible to these sprays are most vulnerable.
Bob Morris is a horticulture expert living in Las Vegas and professor emeritus for the University of Nevada. Visit his blog at xtremehorticulture.blogspot.com. Send questions to Extremehort@aol.com.
Pollen alert. That’s what we see on our advisories in the early spring. Pollen season might last until May. Right now we’re in mulberry season.
Why doesn’t my Meyer lemon tree produce any fruit? I was reminded of this question when I estimated the fruit production this year in a Las Vegas orchard.
The difference between Southwestern desert plants and other types of plants used for landscaping is the timing, or when the water is applied.
Lumps or bumps on the trunk are probably epicormic nodules, places on the trunk covered by thin bark that have a cluster of buds under it. These buds will sometimes grow into shoots. On some trees removing these shoots as soon as they are seen may cause these nodules to stop producing shoots or fewer of them.
I like deals. Buying a large tree in a box and getting it planted for free is a good deal. Just have it done right.
It’s a good idea in our climate to delay the final pruning of wine grapes and table grapes until freezing, dry and windy weather has passed.
Final pruning of fruit trees for less-experienced pruners is best delayed until flowers appear. It’s a lot easier to see where fruit will be produced when actual flowers are seen.
This winter, the valley hasn’t had any freezing temperatures at lower elevations. But let’s not forget about chilling injury (damage occurring somewhere around 50 to 45 degrees Fahrenheit) in new growth and fruits of tropical plants like tomatoes.
The bottle tree you are buying from the nursery — Brachychiton populneum — is not really a bottle tree at all. The true bottle tree (B. ruprestis) is very different from the nursery version because its trunk is truly shaped like a bottle. I