Weather maps, freezing temperatures and okra

Published 12:50 pm Monday, April 7, 2014

The day after tomorrow is a biggie for vegetable gardeners. Y’all can set out tomato plants Tuesday and feel safe from a late freeze. Of course it you did that in the year 2000, the next day’s low of 27 degrees killed them. According to historical weather data and Mississippi State University, April 8 is the beginning date for planting most warm weather vegetables in Warren County, Hinds and the southern tips of Yazoo and Issaquena. But oddly, it’s 10 days later south to Claiborne and Natchez. Mississippi’s weather map of average last cold spells shows more vertical than horizontal areas.

Maps, advice and averages aside, I’m certain there are tomato plants in the ground already. Several gorgeous afternoons in a row, no football or deer hunting; oh yeah. There’s been tomato plants out there a while with plastic milk jugs at the ready.

Two spring garden vegetables that can “officially” be planted before April 8 are sweet corn and snap beans. Not only do both tolerate cool weather, but they despise the heat of mid-summer. Corn originated and was domesticated somewhere between southern Mexico and the northern bit of South America. We tend to think plants that came from south of here are heat-tolerant. But corn developed high in the mountains and was not exposed to extreme heat. Bell peppers also came from up in the mountains in same general vicinity. Veteran gardeners know bell pepper plants don’t croak from summer’s heat, but bloom and pepper production slack way off and pick back up in early fall.

The historical average last threat of freeze and the level of genetic cool tolerance mostly determine the recommended earliest planting date for our different vegetables. And low genetic heat tolerance matters in determining how late a given vegetable should be planted. But for most species, the latest planting date depends on the length of time it takes a plant to produce edible vegetables. Those that grow and produce rather quickly can be planted well past spring. That means late August for squash and cucumbers and early August for purple hull peas and transplants of tomato and pepper. The first of July is the planting cutoff for pumpkin seeds and sweet potato transplants to have enough time to make. The ones with the longest growing period, and thus a last planting date of May 1, are watermelon, cantaloupe and peanut.

Successive planting refers to planting seeds of one vegetable species about every two or three weeks to lengthen the harvest period. This works well for fast-maturing plants such as southern peas and squash. Double cropping is a same-year second planting in a spot where a crop has been already harvested. The surest way to double crop success is to start with bush snap beans in late March and follow that quickest of crops with something heat-tolerant and fast-maturing, i.e., the squash or purple hulls.

Or just forget all about weather maps, recommended planting dates, successive plantings and double cropping. Plant the whole garden in okra. That’ll work.

Terry Rector writes for the Warren County Soil and Water Conservation District, 601-636-7679 ext. 3.