Local planting guide · California
zip 92832
Fullerton is in USDA hardiness zone 10b, with average winter lows of 35°F to 40°F. The local growing season runs roughly 01/17 through 12/19 (~335 days). This zip falls within the California growing region.
- USDA zone
- 10b 35°F to 40°F
- Last spring frost
- 01/17
- First fall frost
- 12/19
- Growing season
- 335 days
- Compatible crops
- 23
- Growing region
- California
Right now in Fullerton
Week 18 priorities
On the docket: transplant out after last frost · direct sow after last frost. See the full calendar →
Gardening in Fullerton
Fullerton's zone 10b classification reflects winter minimums, but the real gardening story is the exceptionally long 335-day growing season coupled with a narrow frost-risk window in mid-January. Last spring frost arrives January 17; first fall frost doesn't appear until December 19. This inversion (frost in winter rather than spring or fall) means summer-heat lovers like tomato, pepper, eggplant, and sweet potato thrive nearly year-round, but late-season tender perennials must survive occasional January freezes. Fig, rosemary, and basil are reliable stalwarts. The dominant constraint is not season length but winter hardiness; varieties selected for California inland heat often falter when the rare hard freeze arrives. Fullerton's proximity to the coast moderates temperature swings, but the 11-month growing window makes it possible to establish perennials, run back-to-back summer crops, and experiment with varieties that would be risky elsewhere.
Regional context · California
What the California brings to Fullerton
From cool foggy coast to hot Central Valley to mountain to desert. Mediterranean climate dominates: wet winters, dry summers. The most productive agricultural state in the country, with reach into citrus and olives that exceed the rest of the country.
Common challenges
Issues that most often defeat home gardeners in zone 10b, drawn from the broader USDA zone profile.
- ▸ No winter chill
- ▸ Tropical pest and disease pressure
- ▸ Saltwater intrusion in coastal soils
What defeats new gardeners in Fullerton
January freezes are the signature threat. Despite zone 10b status, air temperatures can dip to the low 30s during the brief cold snap around mid-month, killing unprotected tender crops like citrus, avocado, and pepper plants that have been growing lush. The second challenge is summer heat; inland Fullerton records regularly exceed 95°F in July and August. Tender crops like tomato and leafy greens require afternoon shade or strategic planting to avoid fruit scald and bitter greens. A third, often overlooked issue is the brief dormancy window in December-January. Perennials like fig and deciduous fruit trees receive minimal chilling hours (the accumulated winter cold they need for spring break), so late-blooming or low-chill varieties become essential.
Crops that grow in Fullerton
23 crops from our catalog match zone 10b, grouped by type.
Tree fruit
12 crops
zone 10b Fig
Ficus carica
zones 7a–10b
zone 10b Lemon
Citrus limon
zones 9a–11b
zone 10b Orange
Citrus sinensis
zones 9a–11b
zone 10b Lime
Citrus aurantiifolia
zones 9b–11b
zone 10b Grapefruit
Citrus paradisi
zones 9a–11b
zone 10b Mango
Mangifera indica
zones 10b–13b
zone 10b Avocado
Persea americana
zones 9b–11b
zone 10b Banana
Musa acuminata
zones 9b–13b
Berries
2 crops
Nuts
1 crop
Vegetables
6 crops
zone 10b Tomato
Solanum lycopersicum
zones 3a–10b
zone 10b Sweet Pepper
Capsicum annuum
zones 4a–10b
zone 10b Hot Pepper
Capsicum species
zones 4a–10b
zone 10b Eggplant
Solanum melongena
zones 5a–10b
zone 10b Sweet Potato
Ipomoea batatas
zones 6a–10b
zone 10b Okra
Abelmoschus esculentus
zones 6a–10b
Herbs
2 crops
Plan the year
Planting calendar for Fullerton
Year-view of seed starting, transplanting, planting, pruning, fertilizing, harvest, and pest-watch windows tuned to Fullerton's local frost dates.
Week ? · loading
This week in Fullerton, CA (zone 10b)
Quiet week in Fullerton, CA (zone 10b). this week is a good time to step back and plan ahead.
Nothing critical on the calendar this week.
128 bars · 23 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 10b
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.
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.
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 (Aphididae)
Small soft-bodied sap-sucking insects that reproduce explosively in spring. Excrete honeydew that supports sooty mold and attracts ants. Transmit viral diseases.
Meloidogyne species
Microscopic soil-dwelling worm that forms galls on roots, reducing vigor and yield.
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.
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.
Anastrepha suspensa
Tropical fruit fly endemic to Florida and the Caribbean. Less aggressive on commercial citrus than Mediterranean fruit fly, but devastating on guava, carambola, and other thin-skinned tropicals.
Top diseases for zone 10b
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.
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.
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.
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.
Verticillium dahliae
Soil-borne fungal disease similar to fusarium wilt but with broader host range and cooler temperature optimum. Persists in soil for 10+ years.
Candidatus Liberibacter asiaticus
Devastating bacterial disease vectored by the Asian citrus psyllid. Once infected, trees decline progressively over several years and there is no cure. Has destroyed commercial citrus across Florida and threatens production worldwide.
Xanthomonas citri
Bacterial disease producing raised corky lesions on leaves, twigs, and fruit. Spread by wind-driven rain and contaminated tools. Quarantine-regulated in many areas.
Xanthomonas euvesicatoria and X. perforans
Bacterial disease causing leaf spots and fruit blemishes on pepper and tomato. Severe in warm humid weather, transmitted via splashing water and seed.
Companion planting suggestions
Beneficial pairings drawn from companion data, filtered to crops that grow in zone 10b.
- 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 Fullerton
Plant tender perennials and citrus by November, not January, to harden off before the cold snap. A single frost-cloth covering during the brief freeze around mid-January is often enough to protect pepper and eggplant plants. Use the long growing season to run overlapping crops: sow tomato seed in December for February transplanting, grow basil through winter for spring harvest, and succession-plant peppers in February and July for fall and winter production. For summer heat management, choose heat-tolerant pepper varieties (Anaheim, Thai, shishito) over Bell peppers, which sunscald above 95°F, and plant in spots that receive dappled afternoon shade or east-facing exposure.
Frequently asked questions
- What crops grow best year-round in Fullerton?
Tomato, pepper, eggplant, basil, rosemary, fig, and sweet potato are the workhorses. Tomato and pepper thrive in the long season; basil and rosemary handle both summer heat and winter chill. Fig produces fruit even in zone 10b with minimal care.
- When is the last frost date, and when should I plant tender crops?
January 17 is the average last spring frost, but it's actually a mid-winter event. Tender crops like pepper and eggplant are best transplanted in February or March, after the frost risk passes and soil warms. Tomato can go in February if protected or March for safety.
- Is January really a frost risk if I'm in zone 10b?
Yes. The average last frost date is January 17, meaning January is when freezes most likely occur. Unprotected pepper, eggplant, and tender perennials are at risk. A single frost cloth on the coldest nights usually suffices.
- How do I manage summer heat for tomatoes and peppers?
Choose heat-tolerant pepper varieties (Anaheim, Thai, or shishito) rather than Bell peppers, which sunscald above 95°F. Plant tomatoes where they receive afternoon shade or dappled light. Provide irrigation every 1 to 2 days during peak summer heat.
- Can I grow vegetables in December and January?
Absolutely. Winter is prime growing season for cool-season crops like leafy greens, brassicas, and root vegetables. Frost protection is needed only for tender perennials and active pepper or eggplant plants that haven't dormanted.
- What about citrus and avocado in Fullerton?
Cold-hardy citrus varieties (Satsuma, Tangerine, Kumquat) survive January freezes readily. Avocado is riskier; fruit-bearing trees are at risk in January and need frost protection or placement in the warmest microclimates (south-facing fence or building wall). North-facing locations are much riskier.
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Frost data: NOAA Climate Normals 1991-2020, station USW00003179. Local microclimates can shift these dates by a week or more.
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