How to Grow St. Keverne
Wikimedia Commons
St. Keverne
Solanum tuberosum 'St. Keverne'
vegetableSt. Keverne is a mid-season potato variety with yellow flesh and thin, smooth skin, originally bred in Cornwall, England. Known for its excellent flavor and versatility in the kitchen, it produces good yields of medium-sized tubers. This heritage variety is prized by home gardeners for its consistent performance and culinary qualities.
When should you plant St. Keverne in your zone?
Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.
Example St. Keverne timeline · Pittsburgh, PA (Zone 6b)
-
Plant St. Keverne
Around Apr 17Near Pittsburgh's average last spring frost.
-
Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
-
Harvest St. Keverne
Around Jul 16≈ 90 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact St. Keverne dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-8, prefers cooler climates with consistent moisture
Sign up free to see if St. Keverne grows in your zone — and get a personalized planting timeline.
Get my St. Keverne timeline →Growth Stages
Seed Piece & Sprouting
2-3 weeksPlanted seed potato develops sprouts and sends out roots underground
Plant when soil reaches 45°F. Ensure seed pieces are disease-free and have at least 2 eyes. Keep soil moist.
Emergence & Vegetative Growth
3-4 weeksShoots break through soil; plants develop leafy green foliage and establish root system
Hill soil around emerging plants twice to prevent greening and light exposure of tubers. Monitor for early blight. Maintain consistent moisture.
Flowering
2-3 weeksPlants produce small white flowers and continue vigorous stem and leaf development
Flowers indicate tubers are actively developing underground. Maintain regular watering and avoid drought stress. Continue hilling if needed.
Tuber Development & Bulking
4-6 weeksFlowers fade, energy redirects to underground tuber expansion and starch accumulation
This is the most critical water period—do not let soil dry out. Maintain 1-2 inches weekly. Watch for late blight in humid conditions.
Maturity & Harvest Readiness
2-3 weeksFoliage yellows and dies back; tubers reach full size with set skin (skin doesn't rub off easily)
Stop watering 2 weeks before harvest to allow skin to cure and harden. Harvest when foliage is mostly dead.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
-
Hand-pick adults and orange egg clusters; use row covers; apply spinosad or neem oil; encourage natural predators like ground beetles
-
Spray with insecticidal soap or neem oil; use reflective mulch; release ladybugs; remove infested plants if severe
-
Remove lower leaves as plant grows; ensure good air circulation; mulch to prevent soil splash; apply copper or sulfur fungicide; rotate crops
-
Plant resistant varieties; maintain proper spacing; avoid overhead watering; remove infected foliage immediately; apply fungicides in humid conditions
-
Crop rotation; remove debris; trap with potato pieces buried in soil; allow soil to fallow; beneficial nematodes in soil
Uses
All-purpose cooking potato
CulinarySt. Keverne's yellow flesh and waxy texture make it ideal for boiling, steaming, and salads where you want tubers to hold their shape. Excellent for traditional British chip shop fries and roasting. [source]
Heritage flavor profile
CulinaryThis variety is treasured by cooks for its rich, distinctly potato flavor that commercial varieties often lack, making it preferred for soups, gratins, and everyday potato dishes. [source]
Garden food security
HouseholdA reliable, high-yielding mid-season variety suitable for home gardeners and smallholders seeking to grow a portion of their own staple carbohydrate source. [source]
Seed potato propagation
CraftSt. Keverne can be saved and replanted as seed potatoes year after year, allowing gardeners to maintain a continuous supply and practice seed saving techniques. [source]
Garden ecosystem contributor
WildlifePotato plants and their flowers support pollinators and beneficial insects while providing food for various garden wildlife, creating a productive edible ecosystem. [source]
Harvest Tips
Harvest when foliage has died back completely (typically late summer/early fall). Dig carefully with a fork to avoid bruising tubers. Store in cool (45-50°F), dark, humid conditions. St. Keverne stores well for 2-3 months. New potatoes can be harvested 2-3 weeks after flowering by gently uncovering tubers without removing the plant.
Fun Facts
- 🌱 St. Keverne was bred in Cornwall, England in the 1960s and is named after a village in Cornwall, reflecting its deep roots in British potato-growing heritage.
- 🌱 This variety became commercially significant in the UK and is still appreciated by seed companies specializing in heritage potatoes, having proven its staying power over 60+ years.
- 🌱 The yellow flesh and distinctive flavor profile of St. Keverne make it a favorite among European potato enthusiasts, particularly in the UK where it remains a cherished local variety.
Join 30,000 gardeners planning their gardens with LizPlants.
Get your personalized St. Keverne planting timeline
Tell us your zip code and we'll calculate exactly when to start St. Keverne seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.
Get my St. Keverne timeline →