Cucumbers need a good warm summer to crop well outside, and to be planted in a sheltered spot. They are not frost hardy, (what does frost hardy mean?) and don't like it cool, so delay planting outside until the warmer weather arrives. This is important when growing cucumbers, because if you plant outside too early there is a real risk of frost or cold damaging the plant. In cooler areas it can be easier to grow cucumbers in containers in a greenhouse.
Also, some varieties of cucumbers are only suitable for growing in a greenhouse or under glass. There are specific varieties for indoors and outdoor growing. The only way to tell is to read the seed packet/growing instructions. Generally speaking if you are growing cucumbers outdoors you will need to grow the ridge varieties, such as illustrated top right which have a tougher skin. In a greenhouse you can grown the smooth skinned varieties illustrated in the center image.
If you are planting outside protect with cloche against wind and chill until established. Like all Cucurbits, water very carefully and sparingly at first as they can have a tendency to rot at the stem, where it meets with the soil, particularly if over watered or the stem and surrounding soil becomes too wet. A good tip if this does happen, or the weather very wet, or just as a precaution, it's worth clearing the soil away from the stem to avoid it resting against the plant until there is strong growth.
Once Cucumbers put on growth the reverse is needed, more water is required to keep the cucumber growing. If growing outside an economical use of space is to grow the cucumber up a wig wam/trellis which has added bonus of keeping fruit off the ground and out of slug reach. ( for tips on keeping slugs at bay)
Cucumbers are vigorous and produce a lot of fruit. In a similar way to growing courgettes, a few plants go a long way and I would limit the number of plants unless you have a passion for pickled cucumbers. Harvest cucumbers simply when they look ready to eat.
Like Courgettes, cucumbers can suffer from powdery mildew and if so pick off worst affected leaves, water and feed. Whether in the plot or under glass, all cucumbers like plenty of water and do not allow them to dry out. It follows that cucumbers can't be left unattended and you will need a friendly neighbour to water if you go away.
A tip when growing cucumbers is to make sure as soon as the flowers form with plenty of baby cucumbers, pinch out the tip of the plant so the plant's energy goes to the fruit development, not more growth. Don't let the plant grow too large at the expense of the fruit. Harvesting regularly which will encourage more fruit.
When growing out doors, similar to courgettes, it's a good idea to remove some of the male flowers.
How do you know the difference? Female flowers have little bump behind them which is the embryo fruit, the males just have stem and flower for image follow this link
Final tip on how to grow cucumbers is they can be easier to grow under glass which helps to control the growing environment. This is especially so if you do not have a sheltered spot on your veg plot.