March is the month when we usually transition from winter to spring gardening.

PlantShrubFinish any necessary pruning this month. The idea with roses is to open up the middle and stimulate new wood. New wood is where the blooms are borne. A pruned rose bush can appear very bare with just 3 or 4 stems extending up from the base at 60 degrees.

With peaches the blooms and fruit are borne on last year’s new wood. Again you prune to open up the middle for light and air movement but you need to leave most of the new wood from last year.  For peaches you want to strengthen the structure to be capable of bearing a reasonable amount of fruit. You also need to leave most of the small stems that grow from the main scaffolds. The stems are called “trashy middles”. The foliage protects the main scaffolds from sunburn.  Visit for detailed instructions and diagrams.

Begin the spray program on peaches when half the petals have fallen off of the blooms. Use carbaryl or malathion for insects and captan for fungus disease prevention. For roses use acephate for insects and triforine for fungus. Organic gardeners can attempt to control insects and diseases with spinosad, neem oil and sulfur products. Follow label instructions on all products.

Petunias_In_containerAfter mid-month we can plant tomatoes in the vegetable garden. In addition to Tycoon, BHN 968, Solar Fire, Bobcat, Valley Cat, Tigress, 444, and Celebrity place the new Rodeo tomato, Red Deuce in the garden. Red Deuce is a determinate selection so it should grow to 6 ft. tall or less.  The fruit, however is very large. Fertilize it well and use tomato cages if you want to maximize production. If you have trouble with nematodes in your garden, select Tycoon, Valley Cat, Celebrity, and BHN 968. They all have resistance to nematodes.

Plant green beans, cucumbers, and summer squash by seed in March. If you have trouble with squash vine borers with your summer squash, consider using tatuma squash.  It is also called calabacita.

Your Brussels sprouts and Swiss chard should continue to produce through the month along with carrots, beets, and turnips. Use the onions in the row for green onions so that the remaining plants have 6 inches space to form large bulbs by the end of May. The leaves will flop over when they are done growing for the year. Harvest them then.

Potatoes signal when the tubers have quit growing when the tops die but you can begin harvest when the first blooms appear.

The winter weeds are evident but did not take over the landscapes because the rains slowed down.  Mow rescue grass and annual bluegrass to keep them under control. They make an excellent winter lawn cover. Bedstraw is the sticky spreading weed that grows over the top of everything in great sheets.  Round-up or Ferti-Lome Weed-Free Zone kills it. The advantages of Weed Free Zone, a 2-4-D product, are that it will not hurt the lawn and it works in relatively low temperatures (40 degrees).  Another option to consider in removing bedstraw is to use a steel-toothed rake to pull it up.  A large bed can be removed in a few minutes.

Wait until after April 15 to fertilize the lawn. Use slow-release lawn fertilizer. Fertilizer applied now will benefit the weeds more than the lawn grass.

If you had problems with crabgrass or sand burs last summer, it is time to apply a pre-emergent herbicide. Amaze, Crabgrass Preventer, and XL all work well.  Make a second application at the end of May.

The snapdragons begin their second flush of blooms in March. They should make a good show through May. Petunias, pansies, primula, geraniums, and cyclamen should also perform well for 3 or more months. You can plant zinnias late in the month for summer color.

Monarch-on-YellowLantanaThe monarch butterfly population has doubled since its low point in 2012 but it still is only 80% of its historic average.  Deforestation at the wintering ground, reduction of milkweed populations because of better weed control in agriculture and challenging weather (drought and cold) have all contributed to the decline. Do your part to help save the Monarchs by planting some milkweeds in the landscape. Nave milkweeds are the most desirable in terms of egg-laying sites for the Monarchs but the tropical milkweed is nearly as valuable and the plants are easier to find.

For butterflies in general plant blooming plants so that you have nectar available 12 months out of the year. The cool weather annuals such as calendula and pansies will do the job in the winter. Salvia greggii is good for spring and fall blooms. Zinnias, cosmos, poinciana, and blue mistflower are excellent as summer nectar sources. Spreading lantana and mealy blue sage provide nectar in the fall and spring.

Written by Calvin Finch
Dr. Calvin Finch is the retired Urban Water Program Director for the Texas A&M Institute of Renewable Natural Resources.You can ask Calvin question and hear his answers on the air as he co-hosts the Gardening South Texas on the air at KLUP (AM 930) Saturday and Sunday from 12:00 to 2:00pm.