What is hardening off seedlings and how is it done

Photo by Markus Spiske on Unsplash

Seeds started indoors have adapted to conditions indoors. These seedlings find it difficult to adapt to external climatic conditions within a day or two. Hardening off seedlings is a process that is followed to help seedlings adapt to external climatic conditions.  Before bringing the seedlings outside make sure the temperature is above 45°F. When your seedlings start to adapt to external conditions, their cell walls start to harden and their plant cuticles thicken. This protects the seedlings against UV rays and moisture loss. Once your seedlings have been hardened off they can be transplanted to garden beds. If you have brought your seedlings from a local nursery then there is no need to harden off your seedlings as it is already done in the nurseries.

How to harden off your seedlings:

On day 1 bring your seedlings outside and keep them in a shady location for an hour or two. Then bring them inside.

On days 2 and 3 you can place your seedlings in a location that gets partial sunlight. Then bring the seedlings inside.

On days 4 to 5 place the seedlings in a location that gets morning sunlight for a few hours. Then bring the seedlings inside.

On days 6 and 7 place the seedlings throughout the day and place the seedlings outside at night.

On day 8 you can transplant your seedlings.

While the hardening-off process is done, make sure to check your seedlings every day for any kind of stress. When plants are stressed they might show burns in their leaves, start to wilt or might even die. If they show that kind of sign make sure to bring them inside. If it’s too windy or if there is heavy rain then bring your seedlings inside. Also, water your seedlings a bit when the moisture levels are low.