Radishes are easily sown directly in soil outside. There is no need to sow them indoors in pots because you can plant them before the last frost, and because they grow so quickly that you’ll be able to grow many rounds before the season is over even if you start late.
One method of starting sprouts is soaking the seeds in water overnight to soften the coat of the seed and promote germination.
Another method is placing them in a soaked paper towel in a plastic bag to see if they sprout before planting them directly in the ground.
Sowing directly in the garden
Radishes don’t want to be grown in pots and transplanted, nor do they need to be, so you can skip right to direct sowing as soon as the ground is workable, four to six weeks before the last frost.
Another way to organize your planting process is to use seed tape, which is a biodegradable strip of seeds that are perfectly spaced apart that you can plant and cover with soil.
Since radishes grow so quickly, they’re better off spread around your garden or in small plots. Growing a large bed of radishes, particularly spring or summer radishes that don’t keep like winter radishes do, may end up overproducing more than you need or can keep fresh.
Radish seeds should be planted in early spring for a spring crop, and then again in late summer for a fall crop. If you prefer to only harvest as much as you plan to eat, you can also plant small crops throughout the season a couple of weeks apart.
Plant seeds about 1 inch between each seed and row, at a shallow depth of about 1/4 to 1/2 inch deep. If you are planting radishes of the larger variety, like many winter radishes, plant seeds 1 inch deep and 4 to 6 inches apart.
Have you tried growing radishes from seed? Is there a way that you prefer? Please share your experiences with us.