Seeds - Part 4: Hardening off your seedlings

Seeds - part 4: Hardening off your seedlings

Hardening off

The purpose of hardening off is to take the plants from the comfort of the greenhouse, where they are nurtured and looked after, and get them used to the harder and cooler conditions outside.

This is particularly important earlier in the season, and will help to free up room in the greenhouse too.

How do you know that they're ready to go out?

Plants are ready to go out once they have developed a really healthy root system. You want the roots to be white or tan in colour, and if the root ball is starting to feel quite tight, this means the plants are definitely ready to go outside.

Wait until the plant is standing up strong and tall though, and is able to bear its own weight.

Watering

When watering in the greenhouse, check the dampness of your plants before watering them again. Often, the surface soil will be dry but the soil beneath will still be damp. Check this by sticking your finger into the soil, up to your knuckle.

Water levels need to be closely monitored in the springtime to prevent your plants from getting too damp. In hot weather meanwhile, take your time with watering to ensure that each plant gets a good soaking.

When it's time to plant out, try and do this on a cooler day, or your plants may suffer from heatstroke.