Local planting guide · Southwest
zip 85066
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 gardening operates on an inverted seasonal calendar compared to most of North America. The frost window is narrow and concentrated in early January (NOAA data shows frost risk from January 3-5), leaving a 365-day de facto growing season. This is not a place where frost limits what grows but heat defines it. Summer temperatures routinely exceed 110°F, which causes blossom drop, fruit sunscald, and germination failure in many familiar crops. Phoenix's zone 9b designation reflects winter minimums of 25-30°F, but these brief winter cold snaps are far less limiting than the months of searing heat. The result is a climate that rewards heat-loving perennials (figs, pomegranates, jujubes, Asian persimmons) and forces familiar temperate crops (tomatoes, peppers, cucurbits) into a counterintuitive fall-to-spring cycle.
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
Summer heat stress is the primary obstacle. When temperatures exceed 100°F from June through August, many fruit trees cease flowering and drop developing fruit. Tomato and pepper plants wilt or produce very little if planted in spring for summer harvest; nearly all productive plantings are pushed to August and September for a fall-winter crop. The second challenge is the sudden freeze risk in January, which can follow warm spells and catch new growth unprepared. Low humidity and intense solar radiation also cause sunscald on thin-skinned fruit and young trees lacking afternoon shade, a problem less common in more humid regions.
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
Reverse the typical vegetable calendar: plant tomatoes, peppers, and other heat-sensitive crops in late August through September to mature during mild autumn and winter months. Spring planting here produces diminished yields as heat stress arrives. Second, apply 30 to 50 percent shade cloth from May through August to protect young trees and sensitive crops from sunburn and heat damage. Third, monitor the January forecast closely and avoid major pruning or new plantings until after the frost risk window (around January 3-5) closes, since sudden cold can damage tender new growth after warm spells.
Frequently asked questions
- What fruit trees grow best in Phoenix?
Figs, pomegranates, jujubes, and Asian persimmons are prolific heat-lovers. Citrus thrives. Apples and pears need low-chill varieties and afternoon shade. Stone fruits (peaches, plums, cherries) work if low-chill varieties are selected and afternoon shade is provided during the hottest months.
- When should I plant tomatoes in Phoenix?
Late August through September is ideal. Spring plantings wilt and drop flowers as heat peaks. Fall-planted tomatoes mature during cool months (October-December) and produce far better yields than heat-stressed spring crops.
- What's the biggest weather risk in Phoenix?
Summer heat, not frost. Extreme heat prevents flowering and fruit set on many crops. The frost window is narrow (early January) and temperatures rarely drop below 25°F. Crop selection and irrigation should center on heat management.
- Do I need frost protection in Phoenix?
Rarely needed. Frost risk is concentrated in early January (around January 3-5 per NOAA data) and temperatures seldom dip below 25°F. Young tender trees or tender perennials may benefit from row covers during unusual late-cold events.
- Can I garden year-round in Phoenix?
Yes. Winter and early spring are the peak growing seasons. Summer (June-August) is dormant for most crops; success requires heat-tolerant varieties or deep shade. Fall and winter (August-February) are the productive main season.
- How often does Phoenix experience frost?
Frost is concentrated in early January, typically occurring a few times per winter season around January 3-5. The rest of the year is frost-free, making Phoenix one of the longest frost-free zones in the continental US.
+−
+−
+−
+−
+−
+−
Frost data: NOAA Climate Normals 1991-2020, station USW00023183. Local microclimates can shift these dates by a week or more.
Related