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When to Plant Tomatoes in Deschutes County, OR

Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.

Deschutes County, Oregon is in USDA Zone 6a. The average last spring frost is June 15 and the first fall frost is September 13, giving you a growing season of approximately 90 days.

At an elevation of 221 feet, Deschutes County receives approximately 54.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Tomatoes to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Tomatoes root diseases.

Deschutes County, OR (Zone 6a) Very short season
90 days
Last Spring Frost June 15
90 growing days
First Fall Frost September 13

Deschutes County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 8 Transplant: Jun 17 🍅 Harvest: Aug 19 – Oct 28
Recommended (50%) ✗ May not fit
Start indoors: Apr 20 Transplant: Jun 29 🍅 Harvest: Aug 31 – Nov 9
Safe Start (90%) ✗ May not fit
Start indoors: May 1 Transplant: Jul 10 🍅 Harvest: Sep 11 – Nov 20

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Deschutes County

How your county's soil matches Tomatoes's growing requirements.

Soil pH

Your soil pH (5.4โ€“6.2) is more acidic than Tomatoes prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Deschutes County is excellent for Tomatoes โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.0%) โ€” Tomatoes will thrive.

How to Plant Tomatoes

0.5"
Planting Depth
24"
Between Plants
36"
Between Rows

How Much Tomatoes to Grow

10-15 lbs
Average yield per plant
3
Plants per person
18 sq ft
Space per person

For a family of 4, plant approximately 12 tomatoes plants in about 72 sq ft. In Deschutes County's 90-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Plant Water Budget

Plant needs
1.2″/week
Rainfall provides
2.6″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Tomatoes

Tomatoes needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.

Month Tomatoes Needs Rainfall You Supplement Action
Jan โ€” 7.6" 0" โ„๏ธ Dormant
Feb โ€” 6.2" 0" โ„๏ธ Dormant
Mar โ€” 4.9" 0" โ„๏ธ Dormant
Apr โ€” 3.8" 0" โ„๏ธ Dormant
May โ€” 3" 0" โ„๏ธ Dormant
Jun 5.2" 2.5" 2.7" ๐Ÿšฟ Regular watering
Jul 5.2" 1" 4.2" ๐Ÿšฟ Regular watering
Aug 5.2" 1" 4.2" ๐Ÿšฟ Regular watering
Sep 5.2" 2.2" 3" ๐Ÿšฟ Regular watering
Oct โ€” 4.9" 0" โ„๏ธ Dormant
Nov โ€” 7.8" 0" โ„๏ธ Dormant
Dec โ€” 9.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Deschutes County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Tomatoes Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Tomatoes needs ~779 GDD — county provides 967 GDD Good fit

Tomatoes Planting Timeline โ€” Deschutes County, OR

Tomatoes Planting Calendar

Activity When Date Range
Start Indoors April 20 Apr 20 โ€“ May 4
Transplant Outdoors June 29 Jun 29 โ€“ Jul 13
Direct Sow June 22 Jun 22 โ€“ Jul 13
Harvest August 31 Aug 31 โ€“ Nov 9

Plant 0.5" deep ยท 24" apart ยท Rows 36" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors
May Start Indoors
June Transplant Outdoors Direct Sow
July Transplant Outdoors Direct Sow
August Harvest
September Harvest
October Harvest
November Harvest
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.2"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“85 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

90 days in Deschutes County

Growing Tips for Tomatoes in Deschutes County

Direct sow Tomatoes outdoors after June 15 in Deschutes County when soil has warmed and frost danger has passed.

Your 90.0-day growing season in Deschutes County is tight for Tomatoes (60.0-85.0 days to maturity). Start indoors and choose early-maturing varieties.

Common pests for Tomatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.

Recommended Tomatoes Varieties for Deschutes County

Choose determinate, early-maturing varieties for your short season

Early Girl (52d) Stupice (55d) Glacier (55d) Sub Arctic Plenty (45d)

Disease-resistant varieties for your humid climate

Mountain Merit (VF) Defiant (LB) Iron Lady (EB/LB/SF)

Companion Planting

Good Companions

Avoid Planting Near

  • Cabbage
  • Fennel
  • Potatoes

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Tomatoes Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Scoop seeds from ripe fruit; ferment 2-3 days to remove gel coating.
Storage Store airtight; viable 4-6 years at 35ยฐF, under 45% humidity.

Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.

Frequently Asked Questions

When should I plant Tomatoes in Deschutes County, OR?

Deschutes County is in Zone 6a with an average last frost of June 15. Plan your Tomatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Deschutes County, OR?

Deschutes County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 15 and first fall frost is September 13.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Deschutes County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Deschutes County, OR. Local conditions may vary. Last updated: April 2026.