If you’re growing cucumbers, you may notice that they can be tricky to grow well. I find that it is easier to grow these amazing plants when you understand their basic needs.
So, in this article, I’ll share some of the fundamental growing conditions for cucumber plants. You’ll learn tips for cucumber planting depth, spacing, watering, lighting, and more. Let’s get into it.
How deep to plant cucumber plants?
When transplanting cucumber plants into the garden, you can plant at the same depth the plant was in its original container. In other words, there is no need to bury the main stem like you would a tomato plant.
If planting from seed, plant cucumber seeds about 1/2″ deep for germination. The larger seed size means the seedlings can push through more soil to emerge. Avoid planting any deeper than 1″, as the seeds may struggle to sprout.
How much space do cucumbers need to grow?
Ideally, cucumbers should be grown vertically. This allows for closer plant spacing, and reduces disease from soil-borne pathogens.
If you are growing cucumbers up a trellis, you can space the plants 18-24″ apart, stem to stem. This much space gives the foliage room to breathe as the plants grow larger.
If growing without a trellis, cucumber plants will sprawl and can take up large sections of the garden. I don’t recommend it, but when growing without a support, space cucumbers with at least 24-36″ between plants.
Feeding cucumber plants
When it comes to nutrients, cucumbers can be hungry! They grow best in highly fertile soil. If you are growing in the ground, I recommend amending with compost in the early spring.
If the plants start showing, you may need to side-dress with a nitrogen rich fertiliser in mid-season. For container plants, more frequent fertilising is required, as the nutrients are used up throughout the season. Find a fertiliser with an NPK ratio roughly around.
How often to water cucumber plants?
Cucumber plants need consistent watering for optimal productivity. In other words, keep your garden soil evenly moist throughout the season.
However, the soil should drain well, as cucumbers don’t do well with overly soggy soil. Drip irrigation can be helpful in sandy soils or in hot, dry climates.
Consistent watering is especially important during the fruiting stage. Without enough water, some of the fruits may abort, leading to lower yields or shriveled cucumbers.
Cucumbers thrive in full-sun conditions.
Keep in mind that cucumbers can grow fairly tall, so it is best to plant them on the North side of the garden (if growing in the Northern hemisphere). This will prevent your cucumbers from shading out smaller crops that are planted nearby.
Cucumbers ready to transplant
Avoid transplanting cucumbers before the soil is warm, ideally around 70°F or warmer. Wait for the soil to warm up to around 70°F, and for overnight temperatures to stay above 65°F. Seeds may also fail to sprout in colder soil, so the same applies when planting from seed.
How tall do cucumber plants grow?
The height of a cucumber plant depends largely on the duration of your growing season. The longer a plant lives in a warm climate, the taller it will grow. For example, cucumbers that are grown in greenhouses are trained to grow vertically on a single main stem. Plants can easily surpass 12 feet in height. However, in the home garden, cucumbers typically grow 6-8 feet tall at maturity. If you want shorter plants, you can prune the main stem (central leader) once it reaches the desired height, thereby stopping any further vertical growth.
Another growing method is known as the “umbrella” training technique. The main stem is grown to a certain height, and is then trained to turn around and grow downwards as it continues to grow.
Pruning cucumber plants
Pruning techniques can be used to improve yields, airflow, and to grow larger cucumbers. In general, most cucumbers benefit from regular pruning.
I recommend removing most or all of the sucker shoots that form on your cucumber vines. These are the side-shoots that form at nodes on the main stem. If you have grown tomatoes, you’ll be familiar with suckers.
Cucumber growing on vine
Sucker shoots will grow off of the main stem, taking energy from it to grow more leaves, flowers and fruits. Suckers will also expand the plant laterally, making for a much larger, wider plant.
By removing suckers, you’ll keep the energy of each plant focused on the main stem and its fruits. This leads to larger fruits and tall, slender plants that are not crowding one another.