How to grow... Cucumber

Rocket Growing Guides


Cucumbers are a very good salad vegetable to grow, and often give you a surprisingly good crop.

  • Growing Advice
  • Common Problems
  • Chef's Corner

Grow under cover if possible

Cucumbers are best grown under cover – in a greenhouse, polytunnel or in a conservatory. If you’re planting them outside be sure to choose a sunny, sheltered spot.


Beds and pots are fine

Cucumbers are easy to grow in planters, raised beds, large pots/containers or grow bags.


How far apart?

About 30-40cm apart.


Water regularly

These are thirsty plants. Water them often to keep the soil evenly moist (but don’t drown them!).


Don't plant out too early

If you don’t have a greenhouse/polytunnel, wait and plant them outside when the risk of frost has passed and the weather has warmed up. Until then, keep them in pots under cover or on a sunny windowsill.


When to harvest

You can easily tell when your cucumber is ready to be harvested by their size. Cut them carefully from the stalk.

Powdery Mildew

This fungal white coating on leaves is nothing to be worried about and is very common in all cucurbits. During the early part of the season, leaves should come through nice and green, and towards the end of the season you start to see powdery mildew creep in. If you do have it earlier in the season, remove affected foliage and keep plants well watered to strengthen them.

Blossom End Rot

This is when the end of the cucumber that was attached to the flower (the blossom end!) starts to rot. It is usually due to a calcium deficiency that is caused by a lack of water. Once the plant has access to enough water it can successfully draw up calcium from the soil. Keep plants well watered and subsequent fruits should be fine.

Yellow/Discoloured Leaves

Any yellow or brown patches forming on the leaves can usually be attributed to a lack of nutrients. Make sure your cucumber plants are getting enough water – the soil should be consistently moist – and use a liquid feed fortnightly once fruits start forming.

Red Spider Mite

Particularly common to dry, warm greenhouses, red spider mites attack the leaves of plants and suck the sap from them. This leaves a mottled appearance, and can cause the plant to drop its leaves and if severe infestations are not dealt with the plant will eventually die. Spray or mist your plants with water to maintain a more humid atmosphere, and be careful not to overcrowd plants in greenhouses. This will help to prevent an outbreak.


These aphids are often a problem. To keep them at bay we recommend planting lots of companion plants – like marigolds – and providing something yellow and sticky, like a yellow bucket smeared in vaseline. Works a treat!

Storage Tips

Harvest them as you want to eat them – they will store in the fridge for a few days, but are much better cooked fresh.

Ways to cook

Great sliced thinly and served with a light dressing, or cut into batons and served with hummus. Or make a raita dip.