How To Grow Cucumbers From Seed In Containers. The preferred way of planting cucumber seeds is planting the seeds directly into a warm soil of about 60 degrees because anything lesser than this will not allow the cucumber to grow and it doesn’t like to be disturbed. Plant the whole thing inside your gardening containers and fill them with a generous amount of organic potting soil, covering them with organic mulch.
If you want an early start, plant the seeds indoors a few weeks before the ground thaws. Large planters with at least 5 gallons of soil capacity work best. For starters, cucumbers should be grown in containers at least 8 inches in depth, and 12″ in circumference.
Choose a pot that is 20 quarts.
Monitor and water or add fertilizer as needed. Cucumbers can flourish successfully in many types of soils. Depending on how protected the containers are and the material with which the container is constructed, you might have to wait until two weeks after the last frost in your area. The plants will die in frost conditions.