Getting rid of nutsedge
Q. My tomatoes are planted in a raised bed. I have had to water them every day. I am used to weeds, but there is a special weed that looks like a grass. It is dark green with pointed leaves. Is there any herbicide that kills this weed? Do you know which weed it is?
A. The weed you describe sounds like nutsedge. It spreads by seed and by bulbs. If you let it go to seed, expect more of the plants and when you pull it by hand, the new bulbs that are left in the yard produce new plants. There are two products that can be used to spray nutsedge in turf grass, Image and Sedgehammer. Neither product is labeled for vegetables. As difficult as it is, the weed needs to be pulled by hand in tomato gardens.
Q. Reassure me again! We can let Bermuda grass go dormant and it will not die, even if all the grass disappears from the drought?
A. Yes, the boulevard section of my lawn resembles a desert with sand dunes again this year, but I don’t have any doubt that the grass will be back in 10 days when the rains begin again.
Q. Which blooming plants can survive and keep blooming in this type of weather, even without irrigation?
A. Once they are established (two years), expect red yucca, esperanza, poinciana, thyrallis, and lantana to bloom without irrigation. The lantana will bloom more with irrigation, but on most sites there will be some bloom whether there is supplemental irrigation or not.
Q. What are the pea-size red balls on the live oak leaves? Should I take some action?
A. The red balls are galls. Small wasps inject their eggs and a cell-altering chemical in the leaf. The chemical changes the leaf cell to grow around the wasp egg. The larva is protected within the gall and serves as a food source until the wasp emerges. The galls are not thought to be a problem to the live oak. A few leaves may fall, but not many.
Q. If you were to pick three container plants for a patio that are most likely to attract hummingbirds this fall, which would you select?
A. For full sun, select firebush, zinnia, and Mexican bush sage. For shade, select penta, fire spike, and lavender lantana. Lavender lantana cannot bloom in deep shade, but does well in light shade.
Calvin Finch is a horticulturist and the San Antonio Water System’s project director of regional initiatives and special projects. Hear him on “Gardening South Texas” on KLUP 930 AM radio Saturdays noon to 2 p.m., and 1-3 p.m. Sundays. Or, e-mail him at email@example.com.