Q&A – Ask Neil: December 11, 2025
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QUESTION 1
CAN UBE YAMS BE GROWN IN NORTH TEXAS?
Question: Can Ube yams be grown in North Texas? What about Okinawan Purple sweet potatoes or Murasaki varieties? Any good place to buy slips for these types? Kent V., Fort Worth.
Answer: Ube, also called “purple yam,” is a starchy vegetable that is a food staple native to the Philippines. I’m not going to try to fool anyone. I am not a cook, nor have I ever grown this plant. But I’ve spent a good bit of time doing my homework in order to answer you.
Ube is commonly combined with condensed milk to make desserts because of its sweet taste and beautiful purple color.
Ube yams grow on vines, not below ground like sweet potatoes. They are, in fact, often confused with Okinawan sweet potatoes. It is less starchy than a traditional yam. It is commonly boiled, then mashed, and then blended to make smooth, creamy desserts.
Because it’s a sub-tropical plant that requires a long growing season to produce full-sized yams, it is best suited to South Texas. In Fort Worth you’ll want to start your plants from slips in a greenhouse or bright garden room a month or more prior to the last killing frost so that you can set them into the garden in late April once the soil has warmed up considerably.
Keep the plants moist at all times to keep them growing actively and feed them with a 3-1-2 or 2-1-2 ratio plant food monthly. Your goal is to keep them vigorous without stimulating excessive growth.
As for a source for the slips, I’m going to have to defer to online sources in late winter or else let you visit with Asian produce marketers. They might be able to get them for you.
By comparison, Okinawan purple sweet potatoes would be much easier. Plant them once soils warm up in April and you’ll have mature roots within 3-4 months. Ube requires 8-10 months, risking frost at both ends of its growing cycle.
Murasaki sweet potatoes were developed by LSU and are very well adapted to North Texas – to Texas in general. They are purple skinned, but creamy white fleshed with a sweet, nutty flavor. They would be an excellent choice and should be easier to find.
QUESTION 2
AM I WASTING TIME PLANTING GRASS NOW?
Question: I have a new house with bare ground all around. Would I be wasting my time putting any grass in with freezing weather soon? Dale J., Rockport.
Answer: Oh, I may lay awake tonight worrying about this answer. To others who don’t know Texas very well, Rockport is on the Texas Gulf Coast way south in the state. Winters are quite mild. They average only a small handful, perhaps even 1 freeze per winter, and then only to 30F to 32F. Temperatures like that would not harm newly planted St. Augustine sod.
And then there was February 2021, when all of Texas suffered catastrophic cold damage. But that was a 1 in 500 years cold spell.
Here is my hybridized answer. If I were in your situation, I would plant St. Augustine on slopes that might erode. I would also plant it near my walks and drive so I wouldn’t have mud. If I had a small lot, I might even sod the entire area. But if I had a larger space, and if no city ordinances required that I plant it all, I’d wait to do the rest until March. By doing those limited plantings you’d be reducing your risks of losing a large investment of time, money, and effort.
Floratam St. Augustine is most frequently planted in South Texas, and it is more tender to cold weather, so that needs to be factored in. You’ll also want to keep the new sod watered regularly to ensure that the shallow roots of the new grass don’t dry out, especially if a cold spell is forecast. You could even lay frost cloth over the sod for an extra measure of protection should you have another of those really rare cold spells (very slim odds).
Finally, all of this presumes you’re planting St. Augustine. All the other types of grasses, notably bermuda and zoysia, would be just fine to plant now where you are.
Folks in the rest of the state, this answer was written specifically for Dale – if you’re not in Rockport or farther south, it doesn’t apply to your area.
QUESTION 3
DO CRAPE MYRTLE TREES NEED TO BE WATERED IN WINTER?
Question: Do crape myrtle trees need to be watered in winter? Leslie S., Princeton.
Answer: Yes. Their root systems are still active, and keeping the plants properly hydrated will help protect them from freeze damage in your area.
QUESTION 4
DID YOU EVER GET TO GO ON FIELD TRIPS WITH YOUR DAD AND HIS STUDENTS?
Question: Your dad will always be my all-time favorite professor at Texas A&M. I was just wondering if you ever got to go on the field trips he took us on to practice identifying plants with our dichotomous key? Jeane R., Rickmond.
Answer: I’m thrilled you have great memories of Dr. Sperry, Professor Emeritus of Botany (Plant Taxonomy) at A&M. That would have been Dr. John Sperry, my uncle. My dad was Dr. Omer Sperry, Professor Emeritus of Range Management at Texas A&M, also a PhD botanist. My dad was 10 years older, but they really looked alike. Great guys, and when we had Thanksgiving dinner together there was a lot of botany discussed. I ate it all up (along with my turkey).
I, too, took Uncle John’s taxonomy class, and I saw a totally different side of him. Great sense of humor and a wonderful sparkle in his eye. I’ll pass your kind comments on to his daughter who shares your first name. She’s the closest person I ever had to a sister. She was one of 6 siblings. I was an only child. Adopted into a great family.
QUESTION 5
SHOULD NELLIE R. STEVENS HOLLIES BE “PLANTED HIGH” IF I HAVE HEAVY CLAY SOIL?
Question: I want to plant a row of Nellie R. Stevens hollies along a fence line in full sun. My lot is totally flat with heavy clay soil, so drainage will be poor. Should I just set the root balls on top of the soil and mound topsoil up around them? Susy K., Grimes County.
Answer: Emphatically, “No!” Maybe it’s because I’ve seen literally thousands of Nellie R. Stevens hollies of all ages that died because they weren’t watered in a timely manner. Thousands! I don’t recall ever seeing even one that died because of poorly drained soil. I guess it would be possible, but you’d have to have standing water for many days after rains. You’d see moss growing on top of the soil. If it’s that bad, you’d have trouble growing turfgrass and conventional shrubs and shade trees due to the high water table. If you’re that concerned about drainage, consider putting a French drain near them. Or cut a shallow and wide swale alongside their planting row to carry away the excess rainfall, but don’t plant them above grade. Hollies as a group are great plants for moist soils. Think about all the hollies you see growing natively from your county and eastward toward Louisiana.
QUESTION 6
HOW OFTEN SHOULD I WATER NEW TREES?
Question: I have 6 young trees, 4 planted two summers ago and 2 planted this spring. How often should I water them deeply, and how many gallons depending on tree size during this winter? Karen R., Cooke County.
Answer: Unfortunately, there is no good answer for you. How large are the trees? What types of trees? What type of soil are they in (as it pertains to water retention)? How large were the root balls when they were planted? How much is it going to rain? Will it be warm and windy or wet and cold this winter? There are so many variables.
We need to judge the soil as our guide in determining when and how much to water. I always leave a basin around my trees for a couple of years so that when I water, I can fill the basin slowly and let the water soak in. If it’s been more than a week since you last had rain, it’s probably time to water deeply and slowly. If they’re growing in sandy soil, that would shorten the interval. Roots remain active even when it’s cold. You’re not going to over-water them if you give the irrigation water a few days to drain away before watering again.