Q&A – Ask Neil: January 4, 2024
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HOW CAN WE ELIMINATE AN ARMADILLO?
Question: What is the best way to get rid of an armadillo that has been digging in my St. Augustine nightly? I know I don’t have grub worms, their favorite food. It is ruining my yard. Gayle D., Fort Worth.
Answer: I will answer your question by sending you to the FAQ answer I have on my website. However, since you’re in the Metroplex, where I also garden, I will tell you that it’s pretty cold to be seeing armadillo damage. They usually hibernate during the winter. If you’re seeing active damage this time of year you might check for possums. If the damage is really intense, and if you’re in some semi-rural part of Fort Worth (as we are to the Dallas side of the Metroplex), you might even suspect feral hogs. They plow through like high-powered rototillers in the middle of the night, but they’re usually not going to be within a city. All of these controls are going to involve trapping of some sort. Once you have the culprit identified, contact your Tarrant County Extension Office for more specific help. I’ve had very good luck trapping possums, raccoons and especially armadillos using the techniques I mention in my FAQ answer along with Havahart traps.
WHAT TALL PLANT WILL STAY ONLY 4 FT. WIDE AND GROW IN THE SHADE?
Question: I want a tall, narrow plant for a shady corner of my yard that’s only 4 ft. wide. I tried Sky Pencil holly, but it gradually died. You recommended Scarlet’s Peak holly, but it’s hard to find. Now I see reference to Skyline holly. Any advice? John M., Frisco.
Answer: Sky Pencil is a Japanese holly hybrid. As such, it is totally intolerant of the alkaline soils along and west of I-35. That’s why it died, and that’s why I say that it should never be sold where soils are alkaline. Scarlet’s Peak and Skyline are both attractive selections of yaupon holly, and both are grown by huge wholesale nurseries with distribution clear across the South. Yaupons are well suited to the shade. As I mentioned here recently, my advice is to strike a good relationship with your local nursery owner and ask them to order one in for you. Yes, these varieties will be in short supply, but they should be available early in the season. Or, for a completely different look, you could consider Oakland holly. It’s not quite as vertical, but it does have an upright habit.
IS IT NECESSARY TO WAIT THIS LONG BEFORE CUTTING PERENNIALS BACK?
Question: My wife taught me perennial gardening 25 years ago. She taught me that you do not cut plants back to the ground until they have died completely, so that all the nutrients can be absorbed back into the roots. Is it necessary to wait this long? Forrest F., Cleburne.
Answer: Green leaves continue to manufacture sugars that are stored for use the following growing season. However, if perennials that normally would have been killed to the ground are still green by January, it’s likely that the old leaves are getting much work done. You could certainly trim off any damaged leaves and twigs, but I would leave any bright green foliage in place. We are destined to have cold weather in the next several weeks. At that point you’ll have more tidy-up work to get done.
SHOULD I CUT BACK SPROUTS FROM A SAPLING REDBUD?
Question: Should I cut back these sapling sprouts from my redbud tree? The tree seemed very stressed this year, even though I added mulch to help with evaporation during the drought. Pam T., Burleson.
Answer: Redbuds have comparatively short life expectancies (30-40 years). But that’s an average. That means that for every one that lives 50 years, there will be a few that live to be 10 or 12 years old. They are prone to several insect and disease problems, most notably red-headed wood borers. Having these sprouts shoot up usually portends the decline of the top growth. However, for now I would remove the sprouts entirely and push all available water and nutrients to the old tree. If you end up losing it, you will see a dozen or more new shoots emerging out of its old stump, so you’ll have ample time to select perhaps three of them to become the new trunks.
IS IT BETTER TO LEAVE FALLEN YEARS ON THE GROUND IN THE BACKYARD?
Question: Is it better to leave fallen leaves on the ground to protect our plants from freezing, then clean them up before spring? Olga G-O, Dallas.
Answer: The short answer is No. Pick them up. The details are in a previous e-gardens answer here on December 28, 2023.
WHAT IS “FINELY GROUND” PINE BARK MULCH?
Question: You often mention “finely ground pine bark mulch” as part of the potting and planting soils that you mix. What is that, and where can I find it? Also, will mealy bugs overwinter in mulch of that sort in my beds? Niki H., McKinney.
Answer: That kind of mulch is a byproduct of the lumber industry. It is the bark that is stripped off, and I prefer the type that comes off and is screened into nickel- and dime-sized pieces rather than larger chunks. For many years I have bought the Jemasco brand that is shipped from Paris, Texas. I buy 50-75 bags at a time, and I use it as a mulch (on top of the ground), as a soil amendment in my beds, and as a component in my potting soils. It’s fairly widely available at independent retail garden centers, nurseries and hardware stores.
As for the mealybugs, like most scale insects, they overwinter beneath bark and in leaf axils. However, around deciduous plants and where plants are killed to the ground, it would seem likely that they could overwinter in plant debris that has been allowed to accumulate on the ground. Tidiness is always a good practice.
HOW CAN I ELIMINATE WHITEFLIES ON MY PLUMERIAS?
Question: I have had a difficult time getting rid of whiteflies on my plumeria plants. How can I do so? Debbie, Morgan Mill.
Answer: I decided the quickest way to find a good answer would be to ask for the help of my unpaid assistant Siri. She doesn’t mind citing information from commercial plumeria growers, but I overlooked that in this case.
This information from Florida Colors Plumeria Nursery seems completely accurate and in great detail.
Hmm. Siri seems to have something going with this nursery, because her second match was also with them. This one, however, is even more thorough. The photos didn’t open on my iMac. It could be time for a reboot at my end, but even without the photos the information is very good.
Aha. I spoke with Siri again, and I told her I wanted university research on whiteflies on plumerias. This one gives great detail on giant whiteflies that first moved into Texas from Mexico in 1991. It is found on a wide variety of plants, including plumerias. The University of California’s ag people prepared this excellent report a couple of years ago. https://ipm.ucanr.edu/pmg/pestnotes/pn7400.html
From these sheets, Debbie, it appears that:
• Close inspection is critical.
• Hitting the stems and leaves with a hard stream of water when you are able to do so outdoors is a good starting point.
• Knowing how to check for natural predators would be good (although I’m not sure how common they will be in new territory).
• Mechanical removal of the egg masses or, in severe cases, leaves or entire stems would be next.
• Finally, resorting to a systemic insecticide such as Imidacloprid when nothing else is available or effective.
I hope that all helps.