cool season · Rosaceae
Growing Strawberry in Utah
Everbearing varieties (Quinault, Eversweet) crop spring AND fall. Pinch flowers the first year for stronger crowns.
Schedule (May 15 last frost)
When to do what
Start indoors
—
Transplant out
5/1
First harvest
7/31
Dates are calibrated for SUS Farms (Sevier County, Zone 6a, last frost May 15). For your own date, use the interactive calendar.
Planting
How deep, how far apart
Method
Start indoors
Seed depth
0.5″
Plant spacing
12″
Row spacing
24″
Germination temp
55–70°F
Days to maturity
90 days
How we grow it
Step-by-step
- 1.
Start indoors 0 weeks before last frost
Seed-starting mix in 2" or 4" cells. Bottom heat at 55–70°F until germination, then drop to room temperature. Light from a clip lamp 14–16 hours a day, 2" from the leaves.
- 2.
Harden off for 7 days before going outside
Day 1: 1 hour outside in shade. Add an hour and more sun each day. Skip the day if it’s windy or below 50°F. After day 7 the plants stay outside.
- 3.
Transplant 12″ apart in rows 24″ apart
Soil should be at least 55°F before transplanting — black plastic mulch laid down two weeks ahead helps in our cool springs. Water in deeply.
- 4.
Mulch and water consistently
2" of straw or wood chip mulch around the base. Drip line at the surface. Aim for 1" per week — including rain — measured at soil level, not by the calendar.
- 5.
Harvest around day 90
Days-to-maturity is a rough guide — taste, color, and size are the real signals. Everbearing varieties (Quinault, Eversweet) crop spring AND fall. Pinch flowers the first year for stronger crowns.
From the farm
What we’ve learned growing strawberry
Strawberry on a working farm means commitment — most fruiting plants take 2-3 years before they start paying back, and they want consistent care across that time. The reward is decades of yield from the right site selection and the right variety. We pick varieties that handle Utah's late frosts and short summers; most of the trendy ones from East Coast catalogs don't make it here.
Pests & problems
Rosaceae family pressures in Utah
Strawberry shares its troubles with strawberry, raspberry, apple, peach, cherry. The pests and diseases below show up most years; the fixes are what we actually do, not what catalogs sell.
Scout weekly during the growing season — most outbreaks are 10x easier to manage when you catch them in week one.
Pest 1
Spotted-wing drosophila (raspberries especially) — fruit fly that lays eggs in ripe fruit. Pick frequently and aggressively; chill or freeze immediately.
Pest 2
Strawberry crown borer — larva tunnels into the crown; plant collapses. Clean up old leaves in fall.
Pest 3
Codling moth (apples) — pheromone traps in March determine spray timing.
Disease 1
Verticillium wilt — sudden wilting, no recovery. Don't plant strawberries where Solanaceae grew in the past 3 years.
Disease 2
Cane blight (raspberries) — wilting canes with sunken brown lesions. Prune out and burn affected canes.
Companion planting
What to plant near (and away from) strawberry
Most companion-planting charts you see online are folklore. The pairings below have either USU Extension research, Cornell vegetable MD pages, or our own multi-year farm logs behind them.
Plant near
Good companions
- ✓Spinach near strawberries (similar growing conditions)
- ✓Onions (deter strawberry pests)
- ✓Borage (attracts pollinators for berries)
Plant away from
Bad companions
- ✗Strawberries near Solanaceae (Verticillium risk)
- ✗Raspberries near walnuts (juglone toxicity)
Crop rotation
Strawberries: 3-year rotation, replant every 4-5 years. Raspberries are perennial; site choice matters more than rotation.
Harvest & storage
Picking, keeping, preserving
When to pick
Days-to-maturity (90 days from transplant) is a baseline. The real signals are color, size, and feel. Everbearing varieties (Quinault, Eversweet) crop spring AND fall. Pinch flowers the first year for stronger crowns.
How to harvest
Clean cuts with sharp pruners or scissors heal faster than ripped stems and reduce disease entry points. Harvest early morning when sugars are highest and the plant is fully turgid; afternoon-harvested produce wilts faster. Don't harvest when leaves are wet — fungal spores ride along.
Short-term storage
Refrigerate at 32-40°F with high humidity (90%+). Most cool-season crops keep 1-3 weeks if cleaned and stored properly. Don't wash before storing — water on leaves accelerates spoilage.
Long-term preservation
Freezing, canning, drying, and fermenting all preserve strawberry. Pick the method that matches your kitchen and how you actually use the harvest — frozen tomatoes are great for sauce but bad for sandwiches; dried herbs work everywhere; fermented vegetables shine in salads.
Mistakes we’ve made
Common ways to fail at strawberry
Each of these has cost us a season at some point. Easier to learn from someone else’s lost crop than your own.
Planting too deep
The fix:Strawberry seeds want exactly 0.5" of cover — about half an inch — about a fingernail deep. Deeper than that and the seedling exhausts itself before reaching light. Carrots and lettuce especially: shallow is right; sprinkle, then cover with a dusting of soil and tamp gently.
Skipping the harden-off step
The fix:Plants raised under indoor lights have soft cuticles and weak stems. Move them straight outside and they sunburn, snap in wind, or wilt and never recover. The 7-day gradual sun exposure is mandatory, not optional.
Watering on a calendar instead of by need
The fix:Stick a finger or screwdriver 4" into the bed. Damp at depth = wait. Dry at depth = water deeply. Calendar watering ignores rain, heat waves, and seasonal evapotranspiration — leading to either drought stress or root rot.
Ignoring soil pH
The fix:Most Utah backyard soil tests at pH 7.4-8.4 (alkaline). Iron and zinc become unavailable to roots above pH 7.5 — leaves yellow, growth stalls. A $20 mailer test from USU Extension tells you exactly what your soil needs. Sulfur amendment in fall, foliar iron mid-season as needed.
Letting heat-bolt happen mid-season
The fix:Cool-season crops bolt (go to seed, become bitter) when night temps stay above 70°F. Plant for an early-spring AND late-summer harvest, with a heat gap in between. Fall plantings of lettuce, spinach, and brassicas are often better than spring ones in Utah.
Common questions
Frequently asked about strawberry
+When should I start strawberry indoors in Utah?
In Sevier County (last frost May 15), start 0 weeks before — that's roughly May. If you're at higher elevation (Park City, Logan), add 2 weeks. Lower elevation (Salt Lake, St. George), subtract 2-4 weeks. Use the interactive seed-starting calendar at /seeds/calendar to dial it in for your specific frost date.
+Why are my strawberry leaves turning yellow?
Three usual suspects. (1) Iron chlorosis — yellow leaves with green veins is the Utah classic; the cause is alkaline soil locking up iron. Foliar iron rescues the season; sulfur amendment in fall fixes it long-term. (2) Nitrogen deficiency — entire leaf yellow including veins, starts with old leaves. Side-dress with compost or a slow-release organic fertilizer. (3) Overwatering — yellowing accompanied by soft, mushy stems means the roots are drowning. Check drainage; reduce water frequency.
+Will strawberry survive a late frost in Utah?
Strawberry is a cool-season crop and tolerates light frost (down to ~28°F) once established. Tender seedlings just out of the greenhouse are more vulnerable — cover with floating row cover when overnight forecasts show below 35°F. After hardening off properly, mature plants of this family typically shrug off late-spring frosts that would kill warm-season crops.
+How long does strawberry take from seed to harvest?
90 days from transplant. Add 0 days for the indoor seed-starting phase, so total time from sowing seed to first harvest is roughly 90 days. Days-to-maturity is a baseline — cool springs add a week or two; hot summers can speed up by similar amounts. Use it for planning, not as a strict calendar.
+What's the spacing between strawberry plants?
12" between plants in the row, 24" between rows. That gives mature plants room to fill in without competing. Closer spacing reduces yield per plant; wider spacing wastes garden space. The numbers come from average mature plant size at full vegetative growth — adjust slightly for compact varieties (closer) or large heirlooms (wider).
Sources:Johnny’s Selected Seeds·USU Extension·Cross-checked with our greenhouse logs.