Local planting guide · Southwest
zip 85033
Phoenix is in USDA hardiness zone 9b, with average winter lows of 25°F to 30°F. The local growing season runs roughly 01/05 through 01/03 (~365 days). This zip falls within the Southwest growing region.
- USDA zone
- 9b 25°F to 30°F
- Last spring frost
- 01/05
- First fall frost
- 01/03
- Growing season
- 365 days
- Compatible crops
- 37
- 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's 365-day frost-free season, with frost risk only around early January, is exceptional within zone 9b. The last spring frost arrives by January 5, and frost doesn't return until January 3 of the following year, creating an essentially year-round growing window. Minimum winter temperatures of 25 to 30°F pose minimal threat to established plants. The real constraint is the opposite of most growing regions: extreme summer heat. From June through August, temperatures regularly exceed 105°F, eliminating most temperate crops and stressing even heat-adapted varieties. This creates an inverted growing calendar. Winter (December through March) is Phoenix's premium season, with cool-weather crops like lettuce, broccoli, and cabbage thriving in 60 to 75°F conditions. Heat-loving perennials such as figs, pomegranates, jujubes, and goji berries occupy summer months. Tomatoes and peppers demand careful variety selection and seasonal timing; spring crops (March to May) must mature before peak heat, and fall plantings thrive through the winter dormancy typical elsewhere.
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 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 Phoenix
Extreme summer heat exceeding 105°F from June through August is the dominant growing constraint. Varieties bred for temperate zones assume peak summer temperatures in the 80s; Phoenix's intense sun causes fruit sunscald, flower drop, and leaf damage in susceptible plants from May through September. Desert soils are typically alkaline (pH 7.5 to 8.5), locking up iron and manganese and causing iron chlorosis even in otherwise-healthy plants. Evaporative loss is severe in low-humidity desert air; surface-applied water vanishes before reaching root zones, and sandy soils don't hold moisture consistently. Spring timing often surprises gardeners: warm April weather tempts early planting of warm-season crops, but cool nights in late April and May stall growth or kill transplants. Irrigation infrastructure inadequacy is common; hand-watering and sprinkler systems prove inefficient compared to the drip systems these conditions demand.
Crops that grow in Phoenix
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 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 9b)
Quiet week in Phoenix, AZ (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 Phoenix
Accept winter as the main growing season. Plant cool-season crops from September through November for ideal maturation in moderate temperatures and minimal water demand; they'll produce through the following spring and early summer. For summer, plant only heat-lovers with minimal chill hours: figs, pomegranates, jujubes, and Asian persimmons thrive on extreme heat and require little supplemental water or frost protection. When growing tomatoes or peppers (March-May or September-November), select heat-tolerant varieties explicitly bred for high temperatures; traditional large-fruited types sunscald reliably in Phoenix's spring sun. Install drip irrigation with heavy mulch (4 to 6 inches) to minimize evaporative loss and maintain consistent soil moisture in sandy desert soils; shallow hand-watering fails in Phoenix's climate.
Frequently asked questions
- What crops produce best year-round in Phoenix?
Heat-tolerant perennials with low chill requirements dominate summer: figs, pomegranates, jujubes, goji berries, and Asian persimmons thrive in 105°F+ heat with minimal water once established. Winter brings cool-season crops (lettuce, spinach, broccoli, cabbage). Tomatoes and peppers require seasonal timing: spring crops (March-May) or fall crops (September-November) with heat-tolerant varieties.
- When should I plant tomatoes in Phoenix?
Phoenix's spring window closes by late May as heat arrives. Plant transplants in March, selecting heat-tolerant varieties like 'Phoenix' or 'Heatwave' rather than standard beefsteak types. For fall crops, plant seeds or transplants in late July or August for September-through-November production after temperatures moderate.
- Does Phoenix get frost?
Frost risk is minimal. The last spring frost is around January 5, and frost doesn't return until early January of the following year, creating an essentially frost-free 365-day season. Tender perennials like figs and pomegranates survive year-round. Frost protection is rarely necessary except in the coldest microclimates.
- Why do spring tomatoes sunburn so easily in Phoenix?
Phoenix's spring sun intensifies earlier and stronger than in temperate climates, and many tomato varieties sunscald at 95°F+. Use 30 to 50% shade cloth from May through August or select small-fruited heat-tolerant varieties. Planting on the east side of taller perennials for afternoon shade also reduces fruit damage.
- What's the single biggest obstacle for Phoenix gardeners?
Summer heat exceeding 105°F from June through August is the dominant constraint, opposite from frost-threatened zones. Most cool-season and many warm-season crops shut down completely. Success requires either accepting summer dormancy or committing exclusively to specialized heat-loving species.
- Can I grow citrus in Phoenix?
Citrus thrives in Phoenix. The 365-day frost-free window and minimal winter chill hours (roughly 0 to 300 annually) suit low-chill citrus varieties perfectly. Trees are fully hardy in zone 9b and produce year-round with essentially no frost risk, making citrus one of the most reliable fruit crops here.
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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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