
Ashleigh Smith

Gardening in high-heat and high-humidity areas can bring a special set of challenges related to plant growth, diseases, and pest control. Gardeners throughout the Southern U.S. are especially familiar with how tricky it can be to successfully grow a healthy garden. Because many plants don’t grow well beyond 85F it is important to select the right plants for the right seasons. Below you will find recommendations for areas that experience extreme heat during the summer months, along with high humidity. This information was gathered using recommendations by the University of Florida, the University of Georgia, Mississippi State University, and Louisiana State University. Each of these universities resides in the topmost hot and humid regions of the United States.
When to Start Seeds in Zones 9+?
Vegetable gardening can look quite different for zones 9, 10, 11, and 12. Unlike more temperate regions, you can grow all year long. This can make it tricky to know what and when to grow. It is best to think of your seasons in terms of cool, warm, and hot. Cool-season vegetables such as brassicas, root vegetables, and traditional leafy greens can be grown during your fall, winter, and spring months. Warm-season vegetables like tomatoes, beans, cucumber, eggplant, peppers, and melons are usually started from seed as early as January and transplanted or directly sown around March-April. Hot-season vegetables include those that can hold up through the summer heat, such as okra, southern peas, some beans, and sweet potatoes. For vegetable-specific planting directions, we recommend using the linked resources below or contacting your local extension office.
Vegetable Varieties for Hot and Humid Southern Climates
Cool-Season
Cool-season vegetables include brassicas, root vegetables, leafy greens, and more. These plants tend to become bitter and bolt (produce flowers rather than foliage) with warm temperatures. These plants can be especially difficult to grow in hot and humid climates. The key to success is growing this type of vegetable during the coolest months of the growing season. As for any home garden plant, cool-season vegetables should be planted according to local recommendations. Below we have gathered some of the top recommendations for cool-season vegetable varieties that do well in some of the states that experience the hottest and most humid climates.
Beets - Detroit Dark Red, Red Ace Hybrid, Ruby Queen
Broccoli - De Cicco, Waltham 29
Brussels Sprouts - Long Island Improved
Carrots - Imperator, Scarlet Nantes, Danvers
Kale - Vates, Dwarf Siberian
Lettuce - Black-seeded Simpson, Parris Island Cos, Red Sails
Mustard - Red Giant, Southern Giant Curled, Florida Broadleaf
Pea - Lincoln, Little Marvel, Green Arrow, Sugar Daddy, Sugar Snap
Radish - Cherry Belle, Champion, Sparkler, Daikon
Spinach - Bloomsdale
Warm-Season
By warm-season we mean warm, not hot. Throughout the southern U.S. summer temperatures can reach an extreme level where most plants are uncomfortable. Conveniently, during this time of the year people also avoid spending time outdoors because the heat is so unbearable for long periods of time. While common vegetable may suffer, tropical plants can thrive during this period of high temperatures. Warm-season vegetables should be planted during the winter, spring and fall seasons. This will help you to get the most out of your growing season while avoiding the extreme temperatures you and your plants would prefer to avoid.
Beans - Winged Bean, Blue Lake(Bush), Blue Lake (Pole), Kentucky Wonder (Bush), Kentucky Blue (Pole)
Corn - Mirai 131 (Y), Early Sunglow (Y), Mirai 301 (Bi), Ambrosia (Bi), Silver Queen (W)
Cucumbers - Boston Pickling, Diva, Ashley, Sweet Success, Marketmore 76, Straight Eight
Eggplant - Black Beauty, Florida Market, Louisiana Long Green
Greens - Malabar Spinach, Amaranth
Okra - Clemson Spineless, Burgundy
Peppers - California Woner, Big Bertha, Jalapeno M, Hungarian Hot Wax, Thai, Long Cayenne, Caribbean Red habanero
Southern Peas - Black-Eye
Tomatoes - Better Boy, Celebrity, Arkansas Traveler, Mortgage Lifter, Early Girl, Rutgers, Juliet, Supersweet 100
Watermelon - Sangria, Crimson Sweet, Baby Doll
Pumpkin - Sugar Baby, Autumn Gold, Jack O Lantern, Dills Atlantic Giant
About the Author

I'm Ashleigh Smith, a native to Northern Utah. I first gained a love of gardening with my grandmother as I helped her each summer. I decided to make a career of it and have recently graduated with a Bachelor's degree in Horticulture from Brigham Young University - Idaho. My studies have focused on plant production while I also have experience in Nursery & Garden Center Operations.
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1 comments
Ken Salinas
the Texas link doesn’t work! 😩
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