May 2012 Gardening Calendar
This column is provided to readers each month. Watch for Gardening In South Texas by Calvin Finch every week in the Wilson County News.
May is lawn month. The weather is usually perfect for lawn growth.
Do not be deceived by the decline of the rescue grass, annual bluegrass, and rye grass to thinking that the lawn is drying out. Those winter weeds decline in the heat just at the same time that St. Augustine, zoysia, and Bermuda grass begin their growth period. Only irrigate the lawn if there has not been any rain for two weeks. Soil moisture level rates are high from the spring rains we have been treated to.
Fertilize the lawn grass early in the month with a slow release fertilizer like 19-5-9. It releases half of the nitrogen when it is applied and watered in, and then slowly releases the rest of the nitrogen over several months. The immediate release supports the high growth period this month. The label will tell you what setting should be used on your spreader. If it does not, set it at the lowest level. You should use five pounds (5 cups) for each 1000 square feet of lawn.
Mow St. Augustine grass at three inches tall, zoysia at two inches, and Bermuda grass at one and a half inches or shorter. Buffalo grass does best when moved at five inches tall.
It is not too late to reduce the sand bur and crabgrass populations this summer if you apply Crabgrass Preventer 2, Weed and Grass Stopper or Amaze to the lawn early this month. Apply it again at the end of June.
In the vegetable garden, reduce the chance of having your tomatoes overwhelmed by spider mites by spraying a solution of two tablespoons of seaweed extract in one gallon of water under the leaves every week. Some gardeners also spray with neem oil every week. It can be sprayed on the top of the foliage. Control hornworms with a Bt product such as Dipel or Bio Worm Control. Stinkbugs require a spray of carbaryl (Sevin) or Malathion when they are spotted.
Remember that moisture has to be consistently available to tomatoes to reduce blossom-end rot. If the soil dries out, the water stream into the plant is broken and the calcium in that stream is denied to the developing fruit. It is especially hard to prevent blossom-end rot in container plants when temperatures move into the 90’s after a cool period.
Snapdragons, stocks, and pansies can be removed from the garden as they decline in the heat. Replace them with zinnias, Cora vinca, moss roses, purslane, and cosmos.
Do not be too eager to cut or remove larkspurs and wildflowers if you want them to naturalize. The seed needs to reach full size in the pod and then begin to brown before it is mature enough to serve as a seed source for next year.
In the shade garden, replace the cyclamen and primula with begonias, coleus or caladium. On the patio, pentas will bloom the entire summer into the fall in containers in the shade. They are very attractive to butterflies and hummingbirds.
The best patio plants for the sun are hibiscus, bougainvillea, Cora vinca, moss rose, and purslane.
For a special experience, plant a patch of Maximilian sunflower seeds in full sun where you can observe them. They grow to seven or eight feet and are not disciplined growers, so may not fit in a manicured landscape but the result can be very spectacular once the seed begins to mature. The seedeaters in your neighborhood will find them. The lesser goldfinches and cardinals are especially attracted but expect chickadees, house finches, buntings, and even woodpeckers to harvest their share.
Herb gardeners will have the same experience but on a smaller scale if you allow your basil to seed. The birds in my yard move up on the patio to get their share. Coneflowers and zinnias will also attract birds to harvest the seeds from the spent flowers.
Keep your hummingbird feeders full with one part sugar to four parts water. Rinse the feeder each week and do a more thorough cleaning with a bottlebrush every month.
Calvin R. Finch, PhD is a SAWS Director and Horticulturist.