Local planting guide · Southwest
zip 85009
Phoenix is in USDA hardiness zone 10a, with average winter lows of 30°F to 35°F. The local growing season runs roughly 01/05 through 01/03 (~365 days). This zip falls within the Southwest growing region.
- USDA zone
- 10a 30°F to 35°F
- Last spring frost
- 01/05
- First fall frost
- 01/03
- Growing season
- 365 days
- Compatible crops
- 28
- Growing region
- Southwest
Right now in Phoenix
Week 18 priorities
On the docket: transplant out after last frost · direct sow after last frost. See the full calendar →
Gardening in Phoenix
Phoenix gardening operates on an inverted calendar compared to most of North America. With last spring frost on January 5 and first fall frost on January 3, the frost window is negligible; the real growing season is the entire year, but split into two productive halves: a lush winter-to-spring growing season (November through April) and a dormant or heavily managed summer (May through October). The summer heat, regularly exceeding 110°F, is the dominant constraint. Many conventional crops fail outright in peak summer, while cool-season crops (lettuce, broccoli, peas) thrive in winter. Heat-tolerant perennials like pomegranate, fig, and Asian persimmon are reliable stalwarts. Tomatoes and peppers require careful timing: planted in fall to mature before June heat, or in late winter to produce through spring before shutdown. The perception that Phoenix has a long growing season is technically true but misleading. The actual productive season is compressed into winter months when temperatures stay mild and daylight hours support vigorous growth.
Regional context · Southwest
What the Southwest brings to Phoenix
Hot, arid, irrigated. Two growing seasons in the low desert: cool October to April, hot May to September. Date palms and citrus thrive at low elevation; apples and stone fruit at higher elevations. The chile-pepper belt of the country.
Common challenges
Issues that most often defeat home gardeners in zone 10a, drawn from the broader USDA zone profile.
- ▸ No chilling for traditional temperate fruit
- ▸ Hurricane exposure
- ▸ Heat-tolerant cultivars only
What defeats new gardeners in Phoenix
The summer heat (115°F+ is not rare) stunts or kills most tender annuals. Tomato plants stop flowering above 90°F night temperatures; fruiting fails entirely from June through August unless the plant is given substantial shade and consistent irrigation. Second, soil tends to be alkaline and low in organic matter. Supplementing with compost and sulfur is often necessary to drop pH enough for acid-loving crops. Third, water scarcity is real. Desert evaporation rates are extreme; drip irrigation is not optional, and hand watering cannot sustain most crops through a Phoenix summer without constant attention. Most home gardeners who fail in Phoenix do so by attempting a traditional spring-summer growing season instead of embracing the winter abundance.
Crops that grow in Phoenix
28 crops from our catalog match zone 10a, grouped by type.
Tree fruit
12 crops
zone 10a Fig
Ficus carica
zones 7a–10b
zone 10a Asian Persimmon
Diospyros kaki
zones 7a–10a
zone 10a Pomegranate
Punica granatum
zones 7b–10a
zone 10a Lemon
Citrus limon
zones 9a–11b
zone 10a Orange
Citrus sinensis
zones 9a–11b
zone 10a Lime
Citrus aurantiifolia
zones 9b–11b
zone 10a Grapefruit
Citrus paradisi
zones 9a–11b
zone 10a Avocado
Persea americana
zones 9b–11b
Berries
3 crops
Nuts
1 crop
Vegetables
10 crops
zone 10a Tomato
Solanum lycopersicum
zones 3a–10b
zone 10a Sweet Pepper
Capsicum annuum
zones 4a–10b
zone 10a Hot Pepper
Capsicum species
zones 4a–10b
zone 10a Eggplant
Solanum melongena
zones 5a–10b
zone 10a Cucumber
Cucumis sativus
zones 3b–10a
zone 10a Summer Squash
Cucurbita pepo
zones 3b–10a
zone 10a Melon
Cucumis melo
zones 5a–10a
zone 10a Watermelon
Citrullus lanatus
zones 5b–10a
Herbs
2 crops
Plan the year
Planting calendar for Phoenix
Year-view of seed starting, transplanting, planting, pruning, fertilizing, harvest, and pest-watch windows tuned to Phoenix's local frost dates.
Week ? · loading
This week in Phoenix, AZ (zone 10a)
Quiet week in Phoenix, AZ (zone 10a). this week is a good time to step back and plan ahead.
Nothing critical on the calendar this week.
147 bars · 28 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 10a
Ranked by how many crops in your zone they affect. Click through for IPM controls and signs to watch for.
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.
Meloidogyne species
Microscopic soil-dwelling worm that forms galls on roots, reducing vigor and yield.
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.
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.
Tetranychus urticae
Tiny mite that feeds on leaf undersides, causing stippling and webbing during hot dry weather.
Ceratitis capitata
Quarantine pest in many regions. Adult females puncture ripening fruit to lay eggs; larvae tunnel through the flesh, causing premature drop and rot.
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.
Top diseases for zone 10a
Ranked by how many crops in your zone they affect. Click through for symptoms, controls, and resistant varieties.
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.
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.
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.
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.
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.
Colletotrichum gloeosporioides
Most damaging mango disease worldwide. Fungal spores infect blossoms and developing fruit during humid weather, producing black sunken lesions that expand on ripening fruit.
Multiple species (Erysiphales)
Surface-feeding fungal disease producing white powdery growth on leaves and stems. Reduces yield by stealing photosynthate and accelerating senescence.
Companion planting suggestions
Beneficial pairings drawn from companion data, filtered to crops that grow in zone 10a.
- 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.
- Okra + Hot Pepper
Both heat-loving warm-season crops with similar water and fertility needs. Hot pepper at okra's base benefits from the slight afternoon shade in extreme summer heat.
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 Phoenix
Plant tomatoes and peppers in late September or early October so they mature and produce through cooler months (November through March), then remove them before May heat. Alternatively, start seeds indoors in late December for a February transplant, giving a brief spring harvest before summer stress sets in. Second, drip irrigation is essential infrastructure. Hand watering in Phoenix summer is economically and logistically unsustainable. Drip systems, combined with shade cloth (30 to 50 percent for heat-tolerant perennials), keep even marginal crops alive through the worst months. Third, choose heat-loving perennials as the foundation: pomegranate, fig, Asian persimmon, and goji berry thrive with minimal coddling in Phoenix heat. They anchor the garden while annual vegetables come and go with the seasons.
Frequently asked questions
- What crops grow best in Phoenix?
Fig, pomegranate, Asian persimmon, and goji berry are essentially foolproof in zone 10a. For vegetables, grow cool-season crops (lettuce, broccoli, spinach, peas, cabbage) from November through March. Heat-tolerant crops like eggplant and okra can persist through summer if shaded and irrigated. Tomatoes and peppers are possible but require fall or early-winter planting.
- When do I plant tomatoes in Phoenix?
Plant tomato transplants in late September or early October so they flower and fruit during the mild winter and spring (November through April). Stop expecting production in May as heat climbs. A secondary, shorter crop is possible from a late-December seed start for February planting, harvesting March through April before summer stress hits.
- What's the biggest gardening risk in Phoenix?
Summer heat stress, not frost. Most home gardeners underestimate the growing-season flip: May through October is a dormancy or survival phase, not a productive one. Planting tomatoes in spring is nearly guaranteed failure. Irrigation failure during peak summer (115°F+) kills even established perennials.
- Is drip irrigation necessary?
Yes. Phoenix's evaporation rate is so high that hand watering or overhead sprinklers waste water and deliver inconsistent moisture. Even drought-tolerant perennials benefit from drip lines during establishment and the hottest months. It's the difference between success and burnout.
- What varieties work for Phoenix peppers and eggplant?
Choose heat-tolerant pepper varieties (Thai chilies, serrano, habanero) and Japanese eggplant lines bred for heat. Plant in late September through October. Many standard bell pepper varieties drop flowers above 90°F night temperatures; Asian and hot pepper types are more resilient to sustained warmth.
- How do I amend alkaline Phoenix soil?
Add sulfur and compost to acidify and improve structure. A soil test (available through University of Arizona Extension) reveals pH and nutrient gaps. Most Phoenix gardeners need 2 to 4 inches of compost mixed into the top 6 to 8 inches, plus sulfur every few years to shift pH down if growing acid-loving crops.
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Frost data: NOAA Climate Normals 1991-2020, station USW00023183. Local microclimates can shift these dates by a week or more.
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