Local planting guide · Pacific Northwest
zip 99336
Kennewick is in USDA hardiness zone 7b, with average winter lows of 5°F to 10°F. The local growing season runs roughly 04/27 through 10/11 (~168 days). This zip falls within the Pacific Northwest growing region.
- USDA zone
- 7b 5°F to 10°F
- Last spring frost
- 04/27
- First fall frost
- 10/11
- Growing season
- 168 days
- Compatible crops
- 83
- Growing region
- Pacific Northwest
Right now in Kennewick
Week 18 priorities
On the docket: transplant out after last frost · direct sow after last frost. See the full calendar →
Gardening in Kennewick
Kennewick occupies a unique position in zone 7b: the rain-shadow interior of the Pacific Northwest, where semi-arid conditions and continental winter cold create a gardening environment quite different from the maritime zone 7b of western Washington. Minimum winter temperatures drop to 5 to 10°F, establishing the cold floor for crop selection, but the binding constraint is summer aridity and a 168-day growing season compressed between April 27 (median last spring frost) and October 11 (median first fall frost). Summers are hot and dry, which suppresses fungal diseases common in humid climates but requires consistent irrigation from June through September. Stone fruits and pome fruits thrive here precisely because of this climate: low humidity means fewer fungal threats to apples, pears, and cherries, and the long, warm days produce sweeter fruit than cooler maritime zones. However, the late April frost date catches early bloomers. Cold-hardy, late-blooming varieties are essential. Peaches, sweet cherries, and Japanese plums carry more risk; European plums, sour cherries, apples, and pears are reliable choices when variety selection is deliberate.
Regional context · Pacific Northwest
What the Pacific Northwest brings to Kennewick
Cool, wet winters and dry summers. Long, mild growing seasons west of the Cascades; short, intense ones east. Famous for berries, hazelnuts, apples, and pears.
Common challenges
Issues that most often defeat home gardeners in zone 7b, drawn from the broader USDA zone profile.
- ▸ Cedar-apple rust pressure heavy in piedmont
- ▸ Japanese beetles
- ▸ Brown marmorated stink bug
- ▸ Late summer disease pressure
What defeats new gardeners in Kennewick
Late spring frost is the single most consistent threat. Apples, pears, and especially stone fruits (peaches, sweet cherries, plums) begin breaking dormancy in March as days warm, and a hard freeze in late April destroys developing flower buds, eliminating the year's crop. European plums and sour cherries are hardier and less prone to catastrophic frost loss. Summer heat and chronic water scarcity stress all but the most drought-tolerant perennials; irrigation is mandatory from June through early September, not optional. Newly planted trees will die in the Kennewick summer without consistent deep watering. Soils in the area tend toward alkaline pH (often 7.5 to 8.5), which can lock up iron and zinc, causing chlorosis on sensitive crops like blueberries and yellowing of new growth on stone fruits.
Crops that grow in Kennewick
83 crops from our catalog match zone 7b, grouped by type.
Tree fruit
15 crops
zone 7b Apple
Malus domestica
zones 3a–9a
zone 7b Pear
Pyrus communis
zones 4a–8b
zone 7b Peach
Prunus persica
zones 5a–9a
zone 7b European Plum
Prunus domestica
zones 4a–8a
zone 7b Japanese Plum
Prunus salicina
zones 5b–9a
zone 7b Sweet Cherry
Prunus avium
zones 5a–8a
zone 7b Sour Cherry
Prunus cerasus
zones 4a–7b
zone 7b Fig
Ficus carica
zones 7a–10b
Berries
12 crops
zone 7b Highbush Blueberry
Vaccinium corymbosum
zones 4a–7b
zone 7b Rabbiteye Blueberry
Vaccinium virgatum
zones 7a–9a
zone 7b Red Raspberry
Rubus idaeus
zones 3b–8a
zone 7b Black Raspberry
Rubus occidentalis
zones 4a–8a
zone 7b Yellow Raspberry
Rubus idaeus
zones 3b–8a
zone 7b Blackberry
Rubus subgenus Rubus
zones 5a–9a
zone 7b June-Bearing Strawberry
Fragaria x ananassa
zones 3a–8b
zone 7b Everbearing Strawberry
Fragaria x ananassa
zones 3b–9a
Nuts
6 crops
Vegetables
40 crops
zone 7b Tomato
Solanum lycopersicum
zones 3a–10b
zone 7b Sweet Pepper
Capsicum annuum
zones 4a–10b
zone 7b Hot Pepper
Capsicum species
zones 4a–10b
zone 7b Eggplant
Solanum melongena
zones 5a–10b
zone 7b Potato
Solanum tuberosum
zones 3a–9a
zone 7b Cabbage
Brassica oleracea var. capitata
zones 3a–9b
zone 7b Broccoli
Brassica oleracea var. italica
zones 3a–9a
zone 7b Cauliflower
Brassica oleracea var. botrytis
zones 3b–9a
Herbs
10 crops
zone 7b Basil
Ocimum basilicum
zones 4a–10b
zone 7b Parsley
Petroselinum crispum
zones 3b–9b
zone 7b Cilantro / Coriander
Coriandrum sativum
zones 3b–9b
zone 7b Dill
Anethum graveolens
zones 3b–9a
zone 7b Oregano
Origanum vulgare
zones 4a–9b
zone 7b Thyme
Thymus vulgaris
zones 4a–9a
zone 7b Rosemary
Salvia rosmarinus
zones 7a–10b
zone 7b Sage
Salvia officinalis
zones 4a–9a
Plan the year
Planting calendar for Kennewick
Year-view of seed starting, transplanting, planting, pruning, fertilizing, harvest, and pest-watch windows tuned to Kennewick's local frost dates.
Week ? · loading
This week in Kennewick, WA (zone 7b)
Quiet week in Kennewick, WA (zone 7b). this week is a good time to step back and plan ahead.
Nothing critical on the calendar this week.
418 bars · 83 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 7b
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.
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.
Sylvilagus and Lepus species
Cottontails and jackrabbits strip bark from young fruit trees in winter and graze tender garden vegetables year-round, especially seedlings.
Popillia japonica
Defoliating beetle introduced to North America in 1916. Skeletonizes leaves of many fruit trees, berry canes, and pecan.
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.
Microtus species
Field voles and meadow voles girdle young fruit-tree trunks under snow cover during winter and chew root crops. The leading cause of mysterious orchard losses.
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.
Top diseases for zone 7b
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.
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.
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.
Botrytis cinerea
Ubiquitous fungal disease that causes fruit rot during cool wet weather, often the dominant berry disease in humid regions.
Agrobacterium tumefaciens
Soil-borne bacterium that enters plants through wounds and induces tumor-like galls on roots, crown, and lower stems. Galls reduce vigor and shorten plant lifespan; on Rubus the disease is often fatal.
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.
Plasmodiophora brassicae
Soil-borne disease causing characteristic distorted club-shaped roots on brassicas. Persists in soil for 10-20 years; the dominant brassica pathogen in acidic poorly-drained soils.
Companion planting suggestions
Beneficial pairings drawn from companion data, filtered to crops that grow in zone 7b.
- Peach + Garlic
Garlic planted around peach trees suppresses peach borer and provides general fungal-pressure reduction.
- European Plum + Garlic
Garlic discourages plum curculio and provides general antifungal benefit beneath stone fruit.
- Fig + Rosemary
Rosemary tolerates the dry sites figs prefer and provides aromatic pest deterrence.
- American Persimmon + Pawpaw
Both natives thrive in similar soils and contribute to a polyculture that supports native pollinators and fauna.
- Jujube + Thyme
Thyme groundcover suits jujube's low-water profile and deters cabbage moth and aphid populations.
- Apricot + Basil
Basil's volatile oils discourage stone-fruit pests and support pollinator visits.
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 Kennewick
- Choose late-blooming, cold-hardy fruit tree varieties. Reliance peach, damson plum, and fireblight-resistant apple rootstocks stay dormant longer and bloom after the frost risk passes in late April. This single decision prevents frost loss more reliably than frost cloths.
- Mulch aggressively and commit to a drip irrigation schedule. The Kennewick climate dries surface soil within days; surface watering fails. Lay 3 to 4 inches of wood chip mulch around trees, then run drip lines on a timer for deep, infrequent watering (once or twice weekly in peak summer). This cuts hand-watering labor and improves establishment.
- A frost cloth stashed in the garage for April serves as insurance. When the 10-day forecast shows frost after April 20, drape lightweight row cover over trees on the evening before the freeze, then remove it the next morning. Protecting one night of bloom can save an entire year's crop on a young tree.
Frequently asked questions
- Which fruit trees grow best in Kennewick?
Apples, pears, and cold-hardy European plum varieties are reliably productive in zone 7b. Peaches work if you select late-blooming cultivars like Reliance. Sweet cherries risk occasional winter damage; sour cherries are the safer choice.
- When should I plant tomatoes in Kennewick?
Wait until late May, after the April 27 median frost date. Transplanting around May 25 provides a 138-day window before the October 11 first fall frost, sufficient for most indeterminate varieties to mature.
- How do I protect fruit trees from late spring frost?
Choose late-blooming varieties first. If frost threatens after bloom begins in late April, drape trees with row cover on the evening before the freeze, then remove it the next morning to allow bee pollination.
- Is irrigation required in Kennewick?
Yes, irrigation is mandatory. The area receives roughly 6 inches of annual precipitation, far below most crop water needs. Plan on deep watering once or twice weekly from June through early September, with additional waterings during heat waves.
- What is the biggest disease threat to fruit trees in Kennewick?
Fireblight is the primary bacterial threat on apples and pears during warm, wet bloom periods in spring. Choose fireblight-resistant rootstocks or scions where possible, and prune infected branches in late winter before bloom begins.
- Can I grow figs in Kennewick?
Hardy fig cultivars like Brown Turkey and Chicago Hardy can survive zone 7b winters. Expect a single light crop by September rather than multiple harvests; place them in warm, south-facing sites and protect them with mulch or burlap in winter.
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Frost data: NOAA Climate Normals 1991-2020, station USW00024163. Local microclimates can shift these dates by a week or more.
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