I thought most folks were familiar with the ancient phrase “for everything there is a season,” but when it comes to gardening, perhaps not. Every month of every year I’m bombarded with questions about planting and growing scenarios and desires that just don’t add up with the realities of gardening in Texas or anywhere for that matter. So, to help with future plants and plans, let’s start with the cold hard facts.
Gardening seasons in Texas can be (and should be) divided up in two ways. Both of these have to be taken into consideration with every horticultural move that you make. No matter how hard you try or how much you know (pay attention Master Gardeners) you cannot make things grow that are not adapted. With July being one of our hottest and driest months, it’s a logical time to preach a fire and brimstone sermon about bad plants burning in hell.
First, let’s deal with moisture. Though there are certainly exceptional years, for the most part, we in Texas live by a wet-dry cycle with wet winters and dry summers. This means that all long-lived perennial and woody plants need to be able to deal with feast or famine when it comes to moisture. Unfortunately, that rules out many true desert and bog plants without much landscape construction and irrigation adjustment. In my humble horticultural opinion, we should only grow plants that are naturally adapted to rainfall alone here and not try to fake it with plants not truly adapted. Good examples would be a plethora of our native species along with many Southern heirloom bulbs and passalong plants.
And with our rainy season generally starting in the fall, it’s imperative that most trees and other woody plants be planted at that time (“fall is for planting”) so that they will be able to take advantage of fall, winter, and spring root growth before having to endure their first life-sucking drought. Certainly, mulching with a coarse organic material helps conserve water, prevent weeds, and keep the soil cooler during the summer; just make sure to avoid excessive “volcano mulching” which does more harm than good.
Our mind-numbing summer heat creates its own issues and is the cause of exponential numbers of plant deaths in Texas, many of which could be avoided through appropriate plant selection. With lots of folks moving to Texas, it’s imperative for them to learn that heat in Texas represents a special kind of evil thanks in part to high nighttime temperatures. You’ll want to be wary of USDA hardiness zones which only indicate how much cold a plant can take and give no indication as to how much heat they can take. As a general rule, the lower the hardiness zone and more cold-hardy a plant is often hints that a plant is from more northern latitudes and evolved with milder summers (think lilacs, rhododendrons, and yews).
Knowing how long it’s going to be hot and dry or cool and moist is extremely important, especially when dealing with herbaceous plants (annuals, perennials, and vegetables) which can all be classified as either cool-season, warm-season, or hot-season plants.
Perennials are pretty much divided into those that grow during the cool season (columbine, verbena, yarrow, etc.), blooming at the end of that cycle, or warm season (cigar plant, lantana, phlox, etc.). For best results and maximum show, you’ll want to plant these plants at the beginning of their growth season, before they even begin to bloom if possible. Perennial bulbs are grouped into spring blooming (fall planted), summer blooming (spring planted), and fall blooming (summer planted) with each ideally planted just before their growth cycle begins.
Annual flowers are also grouped into cool season (cabbage/kale, dianthus, pansies, etc.), warm season (geraniums, marigolds, petunias, etc.), and hot season (ornamental sweet potatoes, periwinkles, tropical milkweed, etc.) with each once again planted at the very beginning of their growing season since the windows of opportunity for growing both cool and warm season annuals is small and closes quickly. Speaking of closing fast, growing vegetables in Texas is all about timing and temperature since, like flowering annuals, they are also divided up into cool, warm, and hot season sorts. We actually have five different veggie growing seasons here with both cool and warm divided into two segments: cool divided by a brief cold in December/January and warm divided by an inferno in June, July, and August. This is why we can (and should) grow two crops of broccoli, cabbage, and turnips in Texas along with two crops of beans, cucumbers, and tomatoes. Plus, the silver lining behind the invisible summer cloud is that due to the length of our hot summers, we can grow two crops of summer peas along with long-season crops like okra and sweet potatoes. It’s extremely critical to use a vegetable planting guide, follow it closely, and plant at the very beginning of the allotted season for each crop. Planting out of season is a proven recipe for failure.
We are currently smack-dab in the middle of the hot season with my beans, corn, cucumbers, and petunias all shutting down and my okra, peas, sweet potatoes, cockscomb, periwinkles, and pride of Barbados in full stride. I went the entire month of June with a total rainfall of one-tenth of an inch. Unfortunately, most lawn and garden plants need one inch per week. July is the month when fall tomatoes and pumpkins are started (with irrigation of course). The next season of change will be in September when cool season veggies and flowers can be planted again.
Bottom line: don’t be distraught when your veggies and flowers die here because they are supposed to. Don’t spend one-second fretting about it. Just grab a calendar (and perhaps a hose) and plant something else!
