Starting Over in the March Vegetable Garden?
Wow. The Arctic Blast of February 2021 was a doozey! Many cool season plants that normally can withstand cold, suffered damage or died during the week of freezing temperatures. I plant fava beans in the fall so that I can get a nice crop as early as January. They normally do just fine, even in a freeze, but not this year. The tops suffered a lot of damage, but have put on new growth in the days following the ice storm. Mature vegetables, like my turnips and beets, hardly seemed to notice.
As a vegetable gardener, I had a decision to make when I heard the arctic blast was on its way to Texas. Last month Patty Leander told us that February can be a transition month between winter cool-season vegetables and spring warm-season plants. You have to decide if you want to sow subsequent cool-season crops like kale or make room for spring. That’s exactly the position I found myself in. My decision was to run out to the garden and harvest everything I could, then leave everything uncovered to fend for itself. I knew that the tender vegetables like lettuce would be toast, but the root vegetables like carrots, beets, and turnips would be fine (hopefully.) None of us knew the severity of the storm, but I’m looking at it as an opportunity to move things toward spring and am starting anew in my March vegetable garden. When life gives you dead plants, make compost and replant!
One or Two More Freezes Likely Coming
It was 80 degrees at my house less than a week after the arctic blast. What? I want to speak to someone in charge.
Our crazy temperature swing might lull us into thinking we are safe from the cold. Maybe we are. Or MAYBE it’s a set-up from our crazy Texas weather. Historically, it starts to warm up this month; our average last day of frost is around March 4. However, we’ve had a hard freeze as late as April, so don’t get complacent in all this lovely March vegetable garden sunshine. Another cold blast this month could kill any cool season crops that managed to survive the arctic blast. And it for sure will end any new vegetables you might have planted that aren’t mature enough for any frost tolerance. And those tomatoes you couldn’t resist buying at the nursery? They are goners too.
The best thing to do for a March vegetable garden is to plan for freezing temperatures. Have your frost protection ready to go and listen to the weather forecast. If any temperature less than 40 degrees is predicted, cover and protect your vegetable garden plants. Some good options are double-folded row covers, sheets, cardboard boxes, old blankets (use a hoop to hold them up if they are heavy), buckets, or plastic jugs. Just be sure to remove the cover the next day when temperatures start to climb. Some years it seems this freeze dance can last for days.
March Vegetable Garden Checklist
Here is what you can do in your vegetable garden this month.
- Water transplants in with a liquid fertilizer solution diluted to half strength.
- Do not add fertilizer to seed beds. Wait until the new plants have true leaves, then use a liquid fertilizer solution to get them started.
- Transplants should be watered in their pots before transplanting and watered again after planting in the ground.
- Water seed beds before planting if they are especially dry. Wait an hour to plant. Water again after planting seeds to facilitate good soil-to-seed contact.
- See the full Vegetable Garden Planting Guide (en español) and Vegetable Varieties for Central Texas.
- Choose planting beds that provide at least six to eight hours of full sun for optimum growth and production.
- Leafy greens like lettuce, chard, mesclun, and mustard can be planted all month. Try planting each week so that they don’t all mature at the same time.
- Plant seeds of peas early in the month, the last crop of beets, collards and turnips mid month, bush and pole beans, cucumbers, summer squash and winter squash later in the month.
- Hold off on melons, okra, sweet potatoes, peppers and southern peas until the very end of the month or the first of April once the soil has warmed up to 65° F and the air temperature is between 70° and 85° F.
- Plant flowers in and around the vegetable garden to attract beneficial insects.
- Tomatoes, peppers and eggplants should go in the garden as transplants so that flowering and fruit set can occur before temperatures get too hot. Plan for frost protection all month.
- Transplant herbs like oregano and thyme late in the month. Hold off on basil until it’s warmer.
- Before adding transplants or seeds, add some compost into your garden bed. Spread up to two inches on top of the soil, then work in with a hand cultivator or hoe.
- Use more compost as mulch around transplants to help protect from cold and suppress weeds.
Diseases/Pests to Look For
Squash Vine Borers
My nemesis is the Squash vine borer, and some years I just give up. However, right about this time I gird myself for battle.
I’ve had pretty good luck using a micromesh row cover. I’ve found it at a few local nurseries and online. Be warned though, it can be expensive and a squirrel can chew through it. The other downside is that it also keeps out pollinators. You’ll need to pollinate the squash blossoms yourself using a small watercolor paintbrush or take a chance removing the cover for a few hours. I pollinate by hand since I have such a problem with the borers.
Another control method, is to till the ground where you are going to plant the squash (if you grow in a container, use fresh potting soil.) Normally I don’t recommend tilling, but it is a good way to destroy any borer that might have overwintered in your soil. I rotate the garden beds I plant squash in and only grow them every other year, but that isn’t enough for my yard. I take my cultivating hoe and work the top three inches of soil to uncover any pupae that may be lurking in the soil. Squishing them provides me some sense of revenge.
This last year I tried trapping them. I found yellow traps that you fill with soapy water and splurged for the optional scent lure. The traps nabbed almost three dozen moths, but some of them had already laid eggs on my pumpkins that I’d left uncovered. I should have worn my glasses and inspected the vines more closely. By the time I discovered the larvae, it was too late. Another squishing incident ensued.
There are some varieties of squash that are resistant to the pest. They may still suffer an attack but are able to survive the infestation. My two favorites are an oval, zuchini-flavored squash called ‘Tatume’. The other is a type of summer butternut squash called ‘Tromboncino’ or ‘Trombetta’. The Tromboncino squash is fun to grow because it gets really long and forms a curl. It’s quite a conversation starter at my house. (Yes, we need other hobbies.)
Other pests to watch for this month are our old friends cabbage loopers, aphids, and whiteflies. Pick off the loopers and use your favorite method to dispatch. Aphids and whiteflies can be controlled with blasts of water.
- Use row cover to protect plants from the wind, if needed.
- Evaluate and audit your vegetable bed irrigation system. Check for misaligned or broken emitters and poor overlap.
- Keep on top of weeds while your plants are putting down roots. Don’t let weeds go to seed, be sure to pull them before they start to flower – especially henbit!
- Wrap tomato cage with row cover and place over transplants to protect them from wind and cold.
- Mound soil around potatoes leaving the top 6-8” of leaves exposed.
- Continue harvesting cool season crops and monitor for pests; as temperatures rise the cool season crops become stressed and attract pests.
- Pull up and compost cool season crops as soon as they start exhibiting stress.
- If you have any brassicas that survived the freeze, let a few go to flower. Beneficial insects love them.
- Start harvesting asparagus when they are bigger than a pencil.
- Continue harvesting broccoli, beets, lettuce, spinach and other cool weather crops; let some of your brassica plants go to flower to attract beneficial insects
to the garden.
Sheryl Williams has been a Travis County Master Gardener since 2010 and currently works as the Horticulture Program Assistant at Texas A&M AgriLife Extension – Travis County. She was introduced to gardening by her mom and grandma and has been an avid vegetable gardener most of her life. Sheryl believes that there is nothing more satisfying than growing and preparing your own food. She likes gardening in Austin year round and concedes that means pulling weeds every day. She practices organic gardening principles and enjoys the challenge of outsmarting garden pests. Occasionally she loses these battles, but doesn’t mind sharing a good meal.