Cucumber
Slicing Cucumber, Pickling Cucumber, English Cucumber, Cucumber
Direct sow after last frost or start 3–4 weeks early. Provide trellis for vining types. Water consistently at soil level — wet foliage causes mildew. Harvest frequently (every 2–3 days) to keep vines producing. Avoid plastic mulch that retains excessive heat.
- Germination
- 3–10 days
- Soil temperature
- 16–35 °C
- Harvest after sowing
- 50–70 days
- Spacing
- 30–45 cm
When to plant cucumber
Sow outdoors 1–2 weeks after your last spring frost.
Dashed line: typical last spring frost in zone 7 (Apr 5). Zone dates are averages; most of the UK is zone 8–9, central Europe 6–7 and the Baltics and Scandinavia 4–6. In the app, Tomatograph uses your garden's own frost dates.
How to grow cucumber
- 1
Sow
Sow 2.5 cm deep in rows or small hills 1–2 weeks after the last frost, once the soil reaches 18 °C. In short summers, start in pots 3–4 weeks earlier.
- 2
Train
Cucumbers are hungry: dig in compost before sowing and side-dress with nitrogen when vines start to run. A trellis keeps fruit clean and leaves dry.
- 3
Water
Water steadily at soil level. Wet leaves invite powdery mildew, and dry spells make fruit bitter.
- 4
Harvest
Pick slicing types at 15–20 cm and pickling types at 5–10 cm, every 2–3 days, starting 50–70 days after sowing. Regular picking keeps vines producing.
Growing conditions
Light
Full sun
Water
High water
Temperature
15–35 °C
Frost tolerance
Frost-sensitive — protect below 0 °C
Days to maturity
55 days
Plant spacing
30 cm
How Tomatograph watches your cucumber
Tomatograph checks your local forecast every morning and only speaks up when one of these applies to your garden.
- Forecast of 2 °C or lowerFrost alert the evening before: cover plants with fleece or bring pots inside.
- 3 days at 35 °C or aboveHeat-wave alert while plants are flowering or fruiting: shade and water early.
- Humidity above 80% for 48 hoursCheck for powdery mildew, which thrives in those conditions.
- Under 5 mm of rain forecast over 3 daysWatering reminder: water deeply at the base, early in the morning.
- Within a week of maturityHarvest-window reminder based on when you planted.
Cucumber questions
- When should I plant cucumber?
- Sow outdoors 1–2 weeks after your last spring frost.
- How long do cucumber seeds take to germinate?
- Usually 3–10 days at a soil temperature of 16–35 °C.
- How long until I can harvest cucumber?
- About 50–70 days after sowing, depending on variety and weather.
- How far apart should I plant cucumber?
- Allow 30–45 cm between plants.
- What grows well with cucumber?
- Good neighbours include dill, lettuce, pea, radish.
Growing guide written by Tomatograph. Planting figures from openplantdb (CC0 1.0). Zone frost dates are averages from openplantdb (CC0 1.0).