• Sow: February - August
• Time to maturity: 3 - 5 months
• Module sow: Only for very early successions
• Spacing: I find 5 seeds per m2 gives me the best yield
• Frost tolerant: not at all, a double layer of fleece is the best protection
• Watering: 1" every 2 weeks in drought, 1” every week last few weeks before maturity
• Plant: in sun or very light shade

Why grow potatoes

I use a rating system to help me decide what to grow and it considers lots of factors, but the main ones are how tasty it is, healthy it is to eat, how expensive it is to buy, how big its harvest is, when its harvest period is and whether I can buy it organically and if not how much it's sprayed.

Potatoes score moderately in this system. They are easy to grow, store well and taste great when harvested early in the season. They are however cheap to buy, vulnerable to disease and when stored for long periods their taste declines compared to professionally stored tubers.

How many to grow?

This is perhaps the most difficult—and arguably the most useful—question to answer. The challenge lies in the sheer variability of potato yields, which are affected by a wide range of conditions. In my experience, potatoes are among the most inconsistent crops. Their productivity can vary significantly due to factors such as:

1. Variety – Some varieties are naturally higher yielding than others.
2. Temperature profile – The pattern of temperatures during the growing period plays a major role.
3. Time of year – Really a composite of light levels, temperature patterns, and disease pressure.
4. Water type – Tap water quality varies by location; rainwater varies by season and geography in terms of acidity and mineral content.
5. Rainwater source – Fresh falling rain is ideal. Potatoes seem to thrive when watered by natural rainfall, while stored rainwater is generally less effective. Unfortunately, we can’t control this.
6. Compost type – Whether it’s fresh or reused, homemade or shop-bought, compost quality affects yields.
7. Light levels – A sunny year produces very different results from a cloudy one, as does growing in full sun versus partial shade.
8. Watering practice – Consistency matters. Potatoes dislike drying out; keeping compost evenly moist improves yields.
9. Compost packing – How tightly compost is packed affects drainage and water retention, which in turn influences growth.
10. Fertiliser – Both type and quantity make a difference.
11. Plant vigour – Some plants are exceptionally vigorous and can skew results, especially in small-scale trials.
12. Harvest size profile – Are you getting lots of small potatoes, or fewer but larger ones?
13. Seed preparation – Chitting, pre-growing in pots, and transplanting methods all influence success.
14. Losses – Greening, pests, or disease can significantly reduce usable yield.