DEAR NEIL: I have two Phalaenopsis orchids that I really enjoy in bloom. However, when they finish flowering I never know how much of the old stem to cut off. This year they are blooming at the ends of the old stems. Do you have any suggestions?
Dear Reader: Great question, because even the American Orchid Society gives you several options. On its website it says that of all the common genera of orchids (one of the largest plant families in the world), only Phalaenopsis plants will produce new flower spikes from old stems. However, sometimes they can originate so far out on the old stems that the spikes become rather gangly.
Some enthusiasts prefer to trim away most of the old stems, leaving a couple of inches at the base (two or three nodes where flowers were attached). When you use this latter option you will have strong, straight stems that are more easily trained to stakes.
I’ve done both. I normally leave the old stem unless it turns brown and shrivels, but when I do leave the old stems my flower spikes are occasionally oddly shaped and hard to manage. It’s your call.
DEAR NEIL: We’re getting our garden ready for spring and we’ve come across grub worms as we’ve rototilled. Should we apply an insecticide?
Dear Reader: No. The feeding portion of their life cycle ended in mid-fall, so they will do no damage to your spring garden plants. Plus, the rototiller probably eliminated a lot of them .
The general rule for treating for white grub worms is that your application of insecticide (when needed) should be made in mid-summer. That’s when the eggs hatch and the tiny worms are near the soil surface.
They feed most actively in August and September (a bit later in South Texas), then they go deeper into the soil and begin to go into pupal cases to emerge late the next spring as adult June beetles, fly, mate and start the process over again.
Also, to affix a threshold number at which damage can occur, you would need to see four or five large grubs per square foot of soil before they would be able to do significant damage. In most cases our plants are able to survive their presence without significant damage.
DEAR NEIL: Why do the leaves hang on one of my Shumard red oaks, when all the others in my yard drop them right on schedule in November and December? It’s rather annoying.
Dear Reader: That’s a genetic difference between that one tree and the others. I have it on a couple of my own red oaks, and like you, I have to keep the blower filled up and at the ready all winter because they’re dropping leaves until the new growth comes out in the spring.
But then I think about how great they are as large shade trees and I quickly forgive them this one small flaw.
DEAR NEIL: I see rhubarb for sale in one of the home centers, but I don’t hear people talking about it here in Texas. Will it grow here?
Dear Reader: Not like it does in colder northern climates. It just can’t handle our summers. As soon as I write that there will be someone who will try it just to defy the laws of nature, but in a career of helping Texas gardeners, I’ve never seen it grow well.
I helped harvest an acre of it on the Ohio State University campus when I was in graduate school, so I know how productive it can be. My mom, who grew up in Nebraska, used to talk about it as I was a young gardener in College Station. Her family had grown it when she was a child, but she knew it wasn’t suited to Texas. Once I saw how well it did in Ohio I understood much better.
DEAR NEIL: We are remodeling and are going to be taking out probably 400 square feet of St. Augustine sod sometime in early February. Can it be dug and replanted successfully at that time? I have an area where I could use it.
Dear Reader: It’s certainly worth a try, especially that late in the winter. The secret will be in taking 2 to 2½ inches of topsoil with it so you’ll get most of its roots. Get it replanted right away and water it well. Its success will depend to a large degree on any extreme cold that might come after it’s been moved.
DEAR NEIL: We had a weeping willow next to a pond where I grew up. The old tree is just about dead now — just one living branch. Is there any way I can start a new tree from it?
Dear Reader: They are rooted from cuttings. I used to root them in a bucket of water, and I’d take cuttings about 1 foot long and the size of a pencil just before their buds started to swell and open in the spring.
Because the stems weep, you have to be careful to stick them into the water in the correct direction (end that was closest to the root system goes into the water). They will sprout roots within a couple of weeks, at which time you can pot them into 2-gallon containers to grow for a couple of months.
They’re one of the few trees that can be started from cuttings, and they’re one of the few plants that I actually root in water.