Plant Answers  >  Gardening Calendar: March

Gardening Calendar


PLANT: March is a month to plant the gardener's favorite vegetables such as tomatoes, sweet corn and snap beans and pepper as well as cucumbers, lima or butter beans, cantaloupe, okra (if the soil has warmed sufficiently --70 degrees F. or higher), southern peas, pumpkin, squash, peanuts and watermelon. The last frost of spring may have already occurred but even if it doesn't frost the wind WILL blow. Protect tender transplants and seedlings with Grow-Web (Plant Guard, ReeMay, Plant Shield) for wind protection, insect avoidance and unexpected cold (4 degree cold protection).

Plant hibiscus, bougainvillea (, mandevilla and allamanda vines in containers for tropical landscape color. In heavily shaded parts of the landscape where grass is difficult to maintain, choose one of the well-adapted groundcover plants such as English or Algerian ivy, Asian jasmine, or mondograss. If deer are a problem in your landscape, try one of the surefire solutions offered at:

Impatiens, fibrous begonias and coleus are summertime favorites for shade. In areas where space is limited, plant your favorite flowers and vegetables in containers or hanging baskets. Use Texas Cooperative Extension recommended varieties. Recommended varieties and sources can be found at:

Perennials which can be planted now include perennial phlox such as 'John Fanick' and 'Victoria' , iris and daylilies. Roses can still be planted. For the best selection of the most enduring roses for Texas, see the rose information at:

Establish or renovate the lawn as needed. Re-sod or replant with turfgrasses adapted to this part of Texas and suited to the planting location (shade or sun). Plant container-grown trees and shrubs as soon as possible. In areas which receive shade where grass is difficult to grow, consider planting a dependable groundcover such as English ivy, Asian jasmine, vinca, or one of the prostrate junipers. When resodding semi-shaded areas with St. Augustine, use ONLY the variety Floratam for best pest resistance. See:

PRUNE: If you didn't get around to pruning your spring flowering and evergreen shrubs during February, do it in early March. However, be sure to prune spring flowering shrubs after they have bloomed. Cutback old chrysanthemum plantings to encourage new growth. A severe pruning now of overgrown beds of groundcovers will remove woody stems and induce new, compact growth from the base whereas later pruning will retard growth. Remove winter damaged plants once you can distinguish the dead wood from the greenwood. Trim over-wintered houseplants to remove lanky growth before moving them outdoors.

FERTILIZE: Use a pre-plant application of a slow-release fertilizer analysis such as 19 - 5 - 9 at the rate of 3 pounds per 100 square feet of garden planting area. Early March is the ideal time to fertilize landscape plants because you give them food just before the spring growing season starts.

ON THE LOOKOUT: Be on the lookout for a spectacular spring wildflower display. The spring months in South central Texas are perhaps best known for their Indian paintbrush, mountain laurel, winecup, pink evening primrose, prairie verbena, horsemint and, of course, the bluebonnets. Travel to Wildseed Farms ( near Fredericksburg to see all of the bluebonnet colors on display. Bluebonnets are actually "winter weeds", so to rid the lawn area of unwanted wildflowers, use a broad-leafed weed-killer spray or simply mow them. If a weed-killer is used, follow label directions carefully to avoid damage to desirable plants.

A wide variety of caterpillars may soon begin appearing throughout the landscape and garden. Check tender foliage on such plants as petunias, broccoli, kale, lettuce, cabbage and cauliflower. Bacillus thuringiensis (Bt.) Is a biological control that works well on most larvae (worm). Slugs, snails and pill bugs can devastate pansies, calendulas, bluebonnets and other cool-season annuals. Try one of the easy-to-use bug baits. Aphids can become a major early spring insect problem on tender spring foliage. Use an insecticidal soap, Neem Oil Spray or an insecticide such as Malathion, diazinon or Orthene.

ODD JOBS: March also is a good time to divide and transplant mums, ajuga, Liriope, daylily and Shasta daisy. Repot overgrown, root-bound pot plants. Keep plants in light shade until re-established.

March Calendar by Dr. Tom Harris

March is a major gardening month in our area. The weather stabilizes and by the end of the month it is warm enough to consider the warm weather plants. The average last freeze date occurs during mid-month. This is the time to prepare beds for planting flowers and vegetables. You may want to go in with a neighbor and rent a tiller for this laborious task-of course a shovel or spading fork will do the same job, it's just harder.

· You can cut tulip foliage down as soon as it is unattractive because they probably won't come back. On daffodils, Dutch iris and other low-chill bulbs, however, leave the foliage until it turns brown. The green leaves are replenishing the bulbs for next year's blooms.

· Fall-planted pansies, snapdragons, dianthus, stocks, alyssum and larkspur are spectacular this month.

· Containerized plants can still be put in the landscape this month.

· It is not too late to plant daylilies and irises if they are well rooted in containers.

· March is great geranium month. Use them in morning sun.

· If the weather is warm after the 15th, consider moving the bougainvillea, plumeria, and hibiscus on to the patio.

· Wildflowers will begin blooming this month. Remember, they must be allowed to mature their seeds if you want new plants next year.

Fruits and Nuts
· You can spray fungicides while the trees are in bloom, but not insecticides. The bees are still pollinating your fruit trees and are susceptible to the sprays.

· It is not too late to spray dormant oil on the trunks of pecans to control phylloxera. Apply one cup of slow release lawn fertilizer per inch of trunk diameter. Spread thinly at the drip line so as not to burn the grass and use a chelated zinc product.

· When peaches are the size of your thumb, thin them to one fruit every 4-6 inches of stem. If you don't thin, you will have a tree full of small fruit and broken branches.

· You can still plant blackberries which are in containers. Keep in mind that late fruits need irrigation to produce large fruit.

· The bluebonnets should begin growing this month after a major growth of the foliage. Do not over-water them as they are xeriscape-type plants.

· Cross vines put on a spectacular show this month, but "Texas Gold" columbines are even more impressive.

· Keep up the spray regimen with roses*Orthene and Funginex are the favorites. Fertilize with rose food every 4-6 weeks according to the label instructions.

· Don't plant caladiums yet-wait until the soil temperature reaches at least 70 F.

· Last chance to dig and divide summer- and fall-flowering perennials.

Shade Trees and Shrubs
· Be careful not to get lawn herbicides too close to trees. Weed-and-feed type fertilizers are notorious for killing young shade trees.

· If you plant container-grown trees this month, be sure to make a 6 ft. circle around the tree for mulch which will keep the grass at bay. Do not add organic material to the planting hole. The tree needs to root in the soil in which it will live the rest of its life.

· Paint all wounds on oak trees immediately to prevent oak wilt.

· Beware of so-called bargains on bare-root trees and shrubs. This late, their chance of survival is pretty low.

· Ball moss is not a parasite on oak trees, but if you don't like the looks of it, spray copper hydroxide (Kocide 101) this month.

· Fertilize trees early this month if you missed it last month. Use one pound (one cup) slow-release lawn fertilizer per inch of diameter spread at the drip line or place in aeration holes.

· Finish any pruning except for the early bloomers such as climbing roses, mountain laurel and ornamental fruits. Prune them after they lose the major flush of blooms.

· Check mountain laurels for worms. Use Bt to control them.

Turf Grass
· It's still too early to fertilize the lawn. It may begin to green up, but the root systems are not fully active until warmer weather arrives. Any greening that occurs this month is due to fall fertilization. "Weed-and-feed" type products only encourage weeds to grow more vigorously. Wait until next month to fertilize.

· March is a good month for aeration and adding a half-inch of compost as a soil dressing if you haven't done so in two years.

· Apply pre-emergent broad-leaf herbicides like Amaze, Balan or Betasan if you didn't apply them last month. Read the labels carefully and be sure your weeds are listed. The weeds that are already up may be killed by the coming heat or with contact herbicides like MSMA or glyphosate. Follow instructions on the label carefully.

· Mow your Asiatic jasmine at the highest level on your mower to encourage a new growth of leaves.

· It's too early to plant Bermuda grass. It will not germinate until late April or early May.

· Tune up the lawnmower and be sure the blade is very sharp. Dull blades tear the grass, sharp ones cut it.

· Check out the automatic lawn sprinkler system for leaks, broken pipes or heads, or wasteful misting.

· Put the containerized tomatoes in the ground towards the end of the month. Save some for April planting and a few for May in case of weather problems.

· Don't forget to keep onions and cole crops well fertilized with one cup of slow-release lawn fertilizer per 10 feet of row this month. Thin out the onions to 4 inches apart. Use the thinned ones for green onions.


Copyright © 2024 - All Rights Reserved. PLANTanswers and are trademarks of Jerry Parsons.