There are 2 ways to growing cucumbers indoors or outdoors. You can grow cucumbers in your garden soil, in containers or pots and in growbags.

One reason why gardeners love growing cucumbers is that home-grown cucumbers taste so much better than shop-bought ones – they actually taste wonderful.

The differences between indoor and outdoor cucumbers are: outdoor cucumbers are generally a shorter variety and indoor cucumber are usually longer but you can also grow the shorter varieties. Some gardeners feel the outdoor varieties often have a better flavour and more crunch. Whilst the indoor varieties are juicier and very nice.

Growing Cucumbers – Starting

You can grow cucumbers from seed or you can buy plants from your local garden centre or nursery or even from car-boot sales.

When buying cucumber seed check that you are buying the right type for you, so if you want outdoor cucumbers buy them, but if you want indoor cucumber then buy those seeds.

The same goes if you want to buy a cucumber plant. It’s really important to buy the right type of cucumber for your garden. This is very important because indoor cucumbers just won’t grow well outside and visa versa.

All Female or Not?

Cucumbers either come as an All-Female variety or not. The all-female variety just produces female flowers (sometimes in the wrong growing condition it can produce a few male flowers) and it’s on the female flowers that the plant produces cucumbers.

The other varieties get male and female flowers – you need to remove the male flowers to prevent any pollination, as this causes bitterness in cucumbers.

Sowing the seeds

Indoor cucumbers – sow the cucumber seeds in pots or in a seed tray in early March. Cucumbers need a constant temperature of around 21-26°C for good germination – that’s why many gardeners start them off in a propagator. Once the seedling has around 2-4 leaves you can then transplant the cucumber seedlings into bigger pots that are filled with compost. They will still need some warmth if it’s very cold.

Indoor cucumbers will need to be kept in a heated greenhouse and then plant them out in late April or plant them out in an unheated greenhouse in late May. Cucumbers aren’t frost-hardy so you have to keep them warm.

Outdoor cucumbers – sow the seeds in pots or seed trays in late March or early April. Because you are sowing them later you often don’t need a propagator but the pots or tray might still need a plastic cover of some sort to keep warmth around the seeds. Transplant them into bigger pots filled with compost when the plants starts getting true leaves.

Soil Conditions

When growing an indoor cucumber many gardeners choose to grow them in growbags. This is a good way of growing them especially as it keeps soil-borne diseases at bay, because you throw the growbag away at the end of the year.

If on the other-hand you are planting your cucumbers outside you need to prepare the soil.

The position needs to be sunny. The soil needs to be free draining. Dig the soil and remove any weeds then add manure or compost so that the soil will be high in organic matter and give the cucumber plants plenty of nutrients to start growing. The pH should be around 6.0 – 7.0.

You should plant out your cucumber plants when there is no chance of any frost. Space the cucumber plants around 2ft apart, so that they have plenty of room to grow.

Looking After The Cucumbers

You need to water the cucumber plants well and feed them at regular times once the fruit starts forming. If you aren’t growing the all-female variety you will need to pinch out the male flowers on your cucumbers.

For indoor cucumbers – you also need to water regularly and you will need to feed the plants with a liquid fertiliser. In very hot weather you will need to up the humidity in your greenhouse by wetting the floor and also you might have to provide some shade for the plants.

Cucumber Support

To give all-female cucumbers some support you can train them up some string. Attach the string to the bottom of the cucumber stem and tie the other-side of the string at a hook of the greenhouse. Then tie the cucumber to the string as it grows.

Tip: The difference between a male and female cucumber – the male just has a flower – the female has a mini cucumber behind the flower. Just pinch the male flower out with your fingers or secateurs as they appear.

Harvesting Cucumbers

Harvest the cucumbers when they are young as they will taste better. If you let too many cucumbers mature fully on the plant, this will stop it from flowering and producing more cucumbers.

 

Pest & Diseases

Whitefly: Is a tiny sap-sucking insect that will create a sticky substance on the leaves, this is known as honeydew, which can hold a sooty mould.

Remedy: You can spray use a fatty acid which is effective for both indoor and outdoor cucumbers. Or buy a suitable pesticide.

Cucumber mosaic virus: Plants and leaves are underdeveloped and deformed, and the leaves show a distinctive yellow pattern.

Remedy: Infected plants should be destroyed – and wash your hands after touching the infected material to avoid infecting other healthy plants.

Slugs: You will need to watch out for slugs and snails outdoors.

Remedy: Either use slug pellets or put down beer traps to catch them.