Rootrainers are a must-have for strong seedlings – they're ideal for sweet peas and beans

Broad bean seedlings growing in open rootrainers, ready to be transplanted into the garden.

Rootrainers are absolute staples in a gardener’s sowing kit: they’re designed to promote healthy root growth and make things a lot easier when it comes to planting indoor-raised seedlings outdoors. What are rootrainers, though?

If you’re hoping to sow seeds successfully indoors and then smoothly move the young plants into the garden, rootrainers are a game-changer. In a nutshell, they’re a type of seed-starting container, and they’re especially useful for plants that grow long taproots, like sweet peas.