Local planting guide · Great Plains
zip 77085
Houston is in USDA hardiness zone 9b, with average winter lows of 25°F to 30°F. The local growing season runs roughly 02/02 through 12/11 (~318 days). This zip falls within the Great Plains growing region.
- USDA zone
- 9b 25°F to 30°F
- Last spring frost
- 02/02
- First fall frost
- 12/11
- Growing season
- 318 days
- Compatible crops
- 37
- Growing region
- Great Plains
Right now in Houston
Week 18 priorities
On the docket: transplant out after last frost · direct sow after last frost. See the full calendar →
Gardening in Houston
Houston gardeners have one of the longest growing seasons in North America. With a last spring frost around February 2 and first fall frost not arriving until December 11, the frost-free period spans 318 days, nearly the entire calendar year. This extended season is a major advantage, especially for warm-season crops like figs, pomegranates, jujubes, peppers, and tomatoes. Zone 9b winters occasionally dip to 25°F, enough to kill tender perennials if left unprotected, but rarely severe enough to cause widespread winter crop loss. The defining constraint is not frost but heat and humidity. Summer temperatures routinely exceed 90°F from June through September, with dew points that create near-tropical conditions. This climate favors heat-loving fruits and promotes fungal diseases on vegetables, particularly powdery mildew on squash and early blight on tomatoes if air circulation is poor. The combination of early spring warmth and nearly year-round growing opportunity makes Houston ideal for multiple plantings of short-season crops.
Regional context · Great Plains
What the Great Plains brings to Houston
Continental, windy, with severe heat and cold extremes. Cold-hardy fruit and small grains north; long warm season for melons, peppers, and pecans south.
Common challenges
Issues that most often defeat home gardeners in zone 9b, drawn from the broader USDA zone profile.
- ▸ Heat stress in summer
- ▸ Insufficient chill for most apples
- ▸ Salt spray near coasts
What defeats new gardeners in Houston
The three biggest challenges for Houston gardeners are summer heat stress, humidity-driven disease, and late-winter frost surprises. Most cool-season vegetables bolt or decline when daytime temperatures stay above 85°F (typically May through September), so timing transitions between spring crops and fall crops requires precision. Powdery mildew, early blight on tomatoes, and fungal root diseases are persistent in the humid subtropical climate, especially in still air or overhead-watered gardens. The second challenge is late-winter frost timing. While February 2 is the historical average last spring frost, late-season cold snaps in March or even early April do occur, killing unprotected citrus blooms or tender new growth. Gardeners who plant warm-season crops too early often lose them to these surprises. A third challenge specific to the Houston area is soil pH; many properties have alkaline to neutral clay soil, which can make iron unavailable to acid-loving plants like blueberries.
Crops that grow in Houston
37 crops from our catalog match zone 9b, grouped by type.
Tree fruit
11 crops
zone 9b Fig
Ficus carica
zones 7a–10b
zone 9b Asian Persimmon
Diospyros kaki
zones 7a–10a
zone 9b Pomegranate
Punica granatum
zones 7b–10a
zone 9b Jujube
Ziziphus jujuba
zones 6a–9b
zone 9b Lemon
Citrus limon
zones 9a–11b
zone 9b Orange
Citrus sinensis
zones 9a–11b
zone 9b Lime
Citrus aurantiifolia
zones 9b–11b
zone 9b Grapefruit
Citrus paradisi
zones 9a–11b
Berries
2 crops
Vegetables
18 crops
zone 9b Tomato
Solanum lycopersicum
zones 3a–10b
zone 9b Sweet Pepper
Capsicum annuum
zones 4a–10b
zone 9b Hot Pepper
Capsicum species
zones 4a–10b
zone 9b Eggplant
Solanum melongena
zones 5a–10b
zone 9b Cabbage
Brassica oleracea var. capitata
zones 3a–9b
zone 9b Kale
Brassica oleracea var. acephala
zones 3a–9b
zone 9b Collards
Brassica oleracea var. acephala
zones 4a–9b
zone 9b Cucumber
Cucumis sativus
zones 3b–10a
Herbs
6 crops
Plan the year
Planting calendar for Houston
Year-view of seed starting, transplanting, planting, pruning, fertilizing, harvest, and pest-watch windows tuned to Houston's local frost dates.
Week ? · loading
This week in Houston, TX (zone 9b)
Quiet week in Houston, TX (zone 9b). this week is a good time to step back and plan ahead.
Nothing critical on the calendar this week.
187 bars · 37 crops
Calendar logic combines NOAA frost normals with crop-specific timing data. Local microclimate and weather always overrules the calendar; use this as a starting point.
Top pests for zone 9b
Ranked by how many crops in your zone they affect. Click through for IPM controls and signs to watch for.
Multiple species (Aphididae)
Small soft-bodied sap-sucking insects that reproduce explosively in spring. Excrete honeydew that supports sooty mold and attracts ants. Transmit viral diseases.
Multiple species (Aleyrodidae)
Tiny white moth-like flying insects that feed on plant sap and excrete honeydew. Transmit numerous viral diseases including tomato yellow leaf curl virus.
Meloidogyne species
Microscopic soil-dwelling worm that forms galls on roots, reducing vigor and yield.
Tetranychus urticae
Tiny mite that feeds on leaf undersides, causing stippling and webbing during hot dry weather.
Multiple species (Chrysomelidae)
Tiny black or bronze jumping beetles that put hundreds of small holes in seedling leaves. Most damaging on direct-seeded brassicas and young eggplant.
Odocoileus species
Whitetail and mule deer browse can devastate orchards and gardens, particularly in winter when food is scarce. Antler rub on young trunks kills saplings outright.
Pseudococcidae spp.
Soft white waxy insects that cluster at leaf joints, fruit stems, and root crowns. Honeydew secretion supports sooty mold; root mealybugs cause decline that mimics drought.
Coccoidea spp.
Sap-sucking insects that attach to bark, leaves, and fruit, secreting honeydew that fuels sooty mold. Heavy infestations weaken trees and cause leaf yellowing.
Top diseases for zone 9b
Ranked by how many crops in your zone they affect. Click through for symptoms, controls, and resistant varieties.
Pseudoperonospora cubensis (cucurbits) and others
Water mold (oomycete, not a true fungus) that thrives in cool damp conditions. Spreads rapidly through cucurbit and brassica plantings on wind-borne spores.
Cucumber mosaic virus, Tobacco mosaic virus, and others
Family of plant viruses producing mottled yellow-and-green leaf patterns. Vectored primarily by aphids; some are seed-transmitted or spread by handling tools and tobacco products.
Pythium and Rhizoctonia species
Soil-borne complex of water molds and fungi that kill seedlings before or shortly after emergence. The single most common cause of seed-starting failures.
Fusarium oxysporum
Soil-borne fungal disease that plugs vascular tissue and kills affected plants. Persists in soil for many years; impossible to eliminate once established.
Sclerotium rolfsii
Soil-borne fungal disease most damaging in warm humid Southern conditions. White mycelial fans and small mustard-seed-sized sclerotia at the soil line are diagnostic.
Calcium deficiency physiological disorder
Not a true disease but a calcium-uptake disorder caused by inconsistent soil moisture during fruit development. The dominant cause of damaged first-fruit on home tomato plantings.
Capnodium spp.
Black fungal coating that grows on honeydew secreted by aphids, scale, mealybugs, and whiteflies. Doesn't infect plant tissue directly but blocks photosynthesis and disfigures fruit.
Tomato spotted wilt orthotospovirus (TSWV)
Virus vectored by thrips, particularly western flower thrips. Wide host range and growing global distribution. No cure once infected.
Companion planting suggestions
Beneficial pairings drawn from companion data, filtered to crops that grow in zone 9b.
- Fig + Rosemary
Rosemary tolerates the dry sites figs prefer and provides aromatic pest deterrence.
- Tomato + Basil
The classic Italian pairing. Basil's volatile oils are reported to repel hornworms and whiteflies, and the two crops share the same warm-season schedule and water needs. Plant basil between tomato cages.
- Sweet Pepper + Basil
Same warm-season culture, same watering schedule. Basil reportedly improves pepper flavor and repels aphids and thrips that are pepper's primary pests.
- Hot Pepper + Basil
Compatible heat-loving culture, similar water needs. Basil interplanted between hot pepper plants supports beneficial insects and reduces aphid pressure.
- Lettuce + Tomato
Lettuce planted at tomato's base benefits from afternoon shade as the tomato grows, extending the lettuce harvest into early summer. Different root depths avoid competition.
- Cabbage + Onion
Onion smell confuses cabbage moth. Both prefer similar moisture and fertility. The onion-cabbage interplanting is a Northern European tradition.
Soil types reference
Soil texture and pH decide what grows easily on your specific lot. Find the closest match below for crop recommendations and amendment guidance.
Practical tips for Houston
Start warm-season crops (peppers, figs, tomatoes) indoors in mid-January to capitalize on the long season, but keep frost cloth handy through February since late-winter freezes, though uncommon, do occur. Plan a second crop of tomatoes, peppers, and heat-tolerant greens by starting seeds in late July and August, aiming for harvest from September through November when summer heat breaks and disease pressure declines. Choose disease-resistant pepper and tomato varieties, ensure good air circulation through the garden by avoiding dense spacing, and water at soil level only (never overhead) to minimize fungal infections in the humid climate.
Frequently asked questions
- What are the easiest crops to grow in Houston?
Heat-loving perennials like figs, pomegranates, jujubes, and Asian persimmons thrive with minimal care in zone 9b. Among annuals, peppers (sweet and hot), okra, and tomatoes (in the spring and again in late summer) are highly reliable if disease-resistant varieties are chosen.
- When should I start tomatoes in Houston?
For spring harvest, start seeds indoors in mid-January for transplanting in late February or early March after the average February 2 last frost date passes. For a second crop harvested in fall, start seeds in late July for transplanting in September, aiming for fruit before the December 11 first frost.
- Is frost a real risk in Houston?
Late-spring frost (after February 2) is rare but occurs; March or April freezes do happen occasionally and can damage tender new growth or citrus blooms. Early-winter frost (before December 11) is similarly uncommon. Keep frost cloth available as an emergency measure, particularly for newly planted tender perennials.
- What causes powdery mildew on my squash and cucumbers?
Houston's humid subtropical climate and still air in crowded gardens create ideal conditions for powdery mildew. Ensure 18+ inches of spacing between plants, water at soil level only, prune lower leaves, and choose resistant squash and melon varieties. Starting a summer rest period (mid-June through August) avoids the worst humidity.
- Can I grow cool-season crops in Houston?
Yes, but not in summer. Lettuce, broccoli, cabbage, and leafy greens thrive from October through April. Planting them too early (before August) leads to bolting when heat arrives; plant them late instead, targeting September/October establishment for winter harvest.
- Why does my citrus struggle in summer?
Citrus can sunscald and drop fruit in extreme heat above 95°F sustained. Afternoon shade cloth (30%) in June and July helps, as does consistent irrigation. Iron deficiency is also common in Houston's alkaline soil; apply chelated iron if leaves yellow.
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Frost data: NOAA Climate Normals 1991-2020, station USW00012977. Local microclimates can shift these dates by a week or more.
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