Cucumbers – how to grow your own

Scientific name (Latin): Cucumis sativus

Family: Cucumber plants (Cucurbitaceae)

Since the 1600s, cucumbers have had a natural place on our plates, but the true origin of the cucumber remains a bit of a mystery. The French-Swiss botanist Alphonse Pyrame de Candolle, in the 19th century, was sure that the cucumber came from India, but others have claimed that it actually comes from Kuwait, Egypt, or Iraq. The truth about the cucumber's origin is uncertain, but one thing is for sure – cucumbers love warmth!

Today, cucumbers come in many shapes and colors, such as round, white, and yellow. In recent years, even more unusual varieties, like jungle cucumbers, have become increasingly popular. And it’s easy to see why, as growing cucumbers is remarkably easy – and there are many new flavors to discover.

Cucumber seeds are sown in regular seed soil or flower soil from the end of March until mid-summer. They grow quickly, so there’s no problem starting a little later; three weeks before you plan to plant them outdoors is usually sufficient.

The plants should be watered regularly, preferably from the bottom, so the seeds and young plants don’t dry out. They also need plenty of light, so place them in a sunny window or under a plant light. This way, they’ll grow plump and healthy. Soon, the vines will need support to climb, such as a flower stick or a thread attached to the curtain rod. The plants will also need support once they are planted outdoors.

When the frost has passed and the soil temperature is around 15 degrees, it's time to plant the cucumber plants outdoors (if the variety you have chosen can tolerate this) or in large pots or containers in a greenhouse or growing tunnels. The containers should have drainage holes at the bottom so that excess water can drain away. It's a good idea to place some drainage material, like leca balls or gravel, at the bottom before filling with soil.

Cucumbers love water and should be watered regularly, preferably daily if they are not to become bitter. But there is a weak spot, and that is the stem. It rots easily if it stays in water. Therefore, it's important to ensure that the plants are not planted lower in the soil than they were before when planting them out. Instead, the plants should be placed slightly higher so that excess water can drain away from the stem.

Cucumbers in pots and containers usually require more nutrients than cucumbers planted outdoors in the ground. Fertilize after a couple of weeks, using, for example, poultry manure, livestock manure, or vegetable fertilizer, and water with fertilizer water regularly throughout the summer. The leaves should be fresh and green, not yellowing.

Before planting out, it is best to gradually acclimate the plants to outdoor conditions. You can do this by leaving them outside during the day for a few days and bringing them in at night. Outdoor cucumbers can also be covered with a fleece cloth during the first period outside to provide extra protection against cold nights.

Cucumbers grow quickly, but there is a pitfall to watch out for when growing them, and it’s related to pollination.

Some cucumbers have only female flowers. These are self-pollinating, so-called parthenocarpic, and don’t require bees or insects to be pollinated. These varieties should not be placed near other cucumber varieties, as cross-pollination between them can result in bitter fruits.

If the cucumbers you've chosen are not self-pollinating and there is a lack of pollinators, for example if you are growing them in a window or a closed greenhouse, you may need to assist with pollination by gently brushing a small paintbrush between the male and female flowers. The female flowers have a small swelling, the beginning of a fruit bud, just under the flower, making them easy to identify.

Nowadays, there are many fun cucumber varieties available, both those suitable for greenhouses and those that can be grown outdoors. In addition, cucumbers come in all shapes and from all corners of the world. How about small jungle cucumbers from Mexico or round cucumbers from the 'Lemon' variety? For those who just want a reliable and good cucumber for salads, the 'Marketmore' variety can be a great choice.

Cucumber varieties are usually divided into grape cucumbers, greenhouse cucumbers, snake cucumbers, and outdoor cucumbers. The latter is often well-suited for pickling.

There is a simple rule when it comes to the common, long cucumbers: Harvest a bit too early rather than too late. It's usually time when the cucumber starts to round at the end, but before it has swelled up too much. If the end has become so thick that the cucumber looks like a bottle gourd or pear at the end, you've waited a bit too long, as the seeds have started to form and the flavor becomes less crunchy and crisp.

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