International Kidney Potatoes: Complete Guide
International Kidney potatoes are a traditional heritage salad potato prized for their outstanding flavour and waxy texture. They are closely associated with early Jersey Royal potatoes and are valued for gourmet cooking rather than heavy yields.
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⭐ Recommended Products — Seed Potatoes & Planting Essentials
• Seed Potato Collection (Early, First & Second Earlies)
A mixed pack of quality seed potatoes to plant for a steady harvest from early summer through to autumn. Ideal if you want variety in size and maturity times.
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• Certified Seed Potatoes (Single Variety Packs)
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• Potato Grow Bags / Containers
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• Potato Fertiliser / Soil Booster
Specially formulated feed to support healthy tuber development and improve yields — apply at planting or as a top-dress during the season.
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• Potato Planting Guides & Markers
Helpful tools and guides that take you through planting depth, spacing, and care — plus reusable markers to keep track of different varieties.
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What Are International Kidney Potatoes?
International Kidney is a first early to early second early potato variety with a distinctive kidney-shaped tuber. It has thin, pale yellow skin and creamy yellow flesh with a firm, waxy texture. The flavour is rich and slightly nutty, making it one of the most highly regarded salad potatoes.
These potatoes are best eaten fresh and are not suitable for long-term storage.
When to Plant International Kidney Potatoes
In the UK, International Kidney potatoes are usually planted:
- Late March to early April, once the soil is workable and frost risk has reduced
Chitting seed potatoes before planting is strongly recommended, as this variety benefits from a strong early start.
How to Grow International Kidney Potatoes
Soil Preparation
International Kidney potatoes grow best in fertile, well-drained soil. Improve soil before planting by digging in well-rotted compost or organic matter to enhance structure and fertility.
Planting Depth and Spacing
- Plant seed potatoes 10–15 cm deep
- Space plants 30 cm apart
- Leave 60 cm between rows
They also grow well in raised beds and large containers.
Earthing Up
As shoots emerge, earth up soil around the stems to protect developing tubers from light. Continue earthing up as plants grow to encourage better yields.
Watering
Water regularly, especially during dry spells and when tubers are forming. Avoid waterlogging, as International Kidney potatoes prefer moist but free-draining soil.
Feeding
Apply a balanced fertiliser at planting time. Avoid excessive nitrogen, which can reduce tuber quality and flavour.
Growing International Kidney Potatoes in Containers
International Kidney potatoes can be grown in containers:
- Use containers at least 40–50 cm deep
- Fill with free-draining compost
- Earth up with additional compost as plants grow
- Water consistently, as containers dry out quickly
When to Harvest International Kidney Potatoes
International Kidney potatoes are usually ready to harvest:
- 12–14 weeks after planting
Harvest when plants are flowering or just after flowering finishes. Tubers should be lifted while skins are thin for the best flavour.
How to Harvest International Kidney Potatoes
- Gently loosen soil with a fork
- Lift carefully to avoid damaging thin skins
- Harvest as needed rather than lifting the entire crop at once
These potatoes are best eaten soon after harvesting.
Common Problems When Growing International Kidney Potatoes
- Dry soil reducing tuber size
- Slug damage in damp conditions
- Blight risk in wet summers, though early harvest reduces impact
Good spacing and airflow help reduce disease risk.
Best Uses for International Kidney Potatoes
International Kidney potatoes are ideal for:
- Salads
- Boiling
- Steaming
- Jersey Royal–style dishes with butter and herbs
They are not suitable for mash, roasting, or long-term storage.
Why Grow International Kidney Potatoes?
- Exceptional flavour
- Classic heritage variety
- Perfect for salads and early summer meals
- Highly regarded gourmet potato
Tips for Best Results
- Always chit seed potatoes before planting
- Keep soil evenly moist
- Harvest early for the best texture and flavour
- Grow alongside other early varieties to extend harvests