How to grow cucumbers


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How to Grow Cucumbers

Easy to grow and with prolific harvests, cucumber lovers will find it easy to grow their own at home with fruits far more superior than anything found in the supermarket.

When and how to sow your seeds

If you have a polytunnel or greenhouse, cucumbers can be sown in a small pot (9cm is a good size) from March somewhere warm, planting out in April or May when the seedlings have 3 or 4 true leaves. If you’re going to grow them on outside wait to plant out until mid-May to avoid any frost damage.

Choose varieties well suited to lower temperatures if you’re planning to grow cucumbers outside. Plants grown inside will generally produce more fruit and begin to crop earlier in the season.


Plant out in 50x50cm spacing into fertile soil with added compost or well-rotted manure. Cucumbers can suffer from transplant shock when planted in their final position, so be sure to handle carefully when planting out.

Some varieties can be left to trail along the ground whereas others will need to be supported with a string or bamboo cane. If you’re using support a good tip is to bury the bottom of the string underneath the root ball when planting to keep it secure.

Plant Care

Cucumbers are thirsty plants and will need regular watering to keep the soil moist. They grow fast, so regular winding on will be needed to keep the plants upright.

Some cucumbers benefit from being regularly pruned to direct the plant’s growth. You can do this by pinching out the tip of a flowering side shoot past the first flower.

Pests and Diseases

Powdery mildew, white fly and cucumber mosaic virus are all common diseases and pests you may encounter when growing cucumbers. Try to become familiar with the signs and symptoms so you can act quickly and keep your plants healthy and productive.


Regular harvesting will encourage cucumbers to produce more fruit so check your plants regularly. Check the characteristics of your variety to see what size your full-size cucumbers should be.

Fruits should feel firm to the touch and uniform in colour, usually with a slightly rounded tip. Cut the stem cleanly with a pair of secateurs or sharp knife.

Seed Saving

To save seed from cucumbers you need to leave them to ripen well beyond the point of eating where they will become much larger and turn a shade of yellow / orange depending on the variety.

Cut the fruits open, scoop out the seeds and pulp into a jar or bucket. Keep in a sunny spot for 2-3 days to ferment, then fill with water and stir well. The good seeds will sink to the bottom, leaving debris, pulp and seeds on the surface. Pour this off along with the water, refill and repeat until you are left with the good seeds at the bottom and clear water. Drain out the water and spread the seeds onto a flat surface to dry.

Seeds will last for several years if dried well and stored in a cool, dry place

Recommended Varieties

  • Marketmore produces luscious, cylindrical, dark green fruits and does so in abundance throughout the summer
  • Crystal Lemon is a prolific, unusual and old variety of outdoor cucumber; small, round and yellow with a crisp, sweet flavour