Squashes, courgettes & cucumbers – start them now for a bumper crop!
Late April onwards is the perfect time for starting squashes, courgettes and cucumbers indoors – on a windowsill or in a greenhouse. These warmth-loving species need sufficient time to develop into strong young plants before mid-May when the last frosts are over and they can be planted outdoors.
Starting these fast-growing vegetables indoors really makes sense as it gives them a good head start, making them more resistant to pests and weather variations.
Why starting indoors pays off
✔ Earlier harvests – Pre-grown plants can go outdoors sooner and produce earlier crops.
✔ Stronger plants – Strong young plants are more robust and resistant to pests and diseases.
✔ Better germination – The controlled environment protects seeds from the cold and predators.
✔ More flexibility – If you start your plants early you can also add further sowings as needed, enabling you to fill any gaps in your plot.
Step-by-step guide to starting your plants indoors
1. Choose the right containers:
Squashes, courgettes and cucumbers have sensitive roots and don’t like being transplanted, so it’s best to use individual pots with a diameter of at least 8–10 cm, or compostable starter pots that can be planted directly in the ground later on.
2. Use the right compost:
It’s best to use a nutrient-rich seed or vegetable compost that’s loose and free-draining. You can mix in a little homemade compost or sand if you’d like to.
3. Sow the seeds:
Sow the seeds at a depth of around 2–3 cm and cover lightly with compost. One seed per pot is enough as the plants grow quickly and need plenty of space.
4. Create the right germination conditions:
- Keep the soil evenly moist but not too wet
- A bright location with a temperature of 20–24 °C is ideal.
- Germination time: 3–10 days, depending on variety and temperature.
- When the first leaves appear move the plants to a place that’s cooler (16–18 °C) but still bright, to stop them getting weak and leggy.
5. Hardening off and planting out:
When the last frosts are over in mid-May the plants can go outside. Key points:
- Harden them off for 1–2 weeks before planting out by standing them outdoors for a few hours during the day.
- A sunny, protected location with free-draining, nutrient-rich soil is ideal.
- Space the plants generously when planting out (at least 80 cm for courgettes and cucumbers, 1–2 m for squashes).
Which varieties work especially well?
Cucumbers:
Vorgebirgstraube, Marketmore, Tanja
- Salad cucumbers for outdoors or snack-sized cucumbers for balconies and raised beds.
To sum up: Start your plants indoors now for a great crop!
If you start your plants indoors in late April you can look forward to strong plants and a bumper crop in summer.
Starting plants indoors gives them the best start in life – and they’ll grow faster and crop sooner because of it.
