Hardening+Off

Although it seems like an unnecessary hindrance, hardening off is an essential step for transplanting success. Seedlings that were begun indoors have grown accustomed to growing in idealized growing conditions – uninterrupted light from grow-lights, small fluctuations in temperature, a lack of pests, and no inclement weather to deal with have helped to start your seedlings growing strong. However, none of these conditions are the same for outdoor growing. If you place your seedlings directly outdoors they may go in to shock. Shock will inhibit plant growth and in some cases could be lethal. For this reason it is important to follow these guidelines to harden your plants.

Hardening plants simply means exposing them to cooler temperatures a little bit at a time over a period of around two weeks. This slows down their rate of growth so that there is less new growth susceptible to shock. Place plants outdoors during the daytime in partial shade. Over a period of a few days move them to full sunlight. A few days before transplanting, leave them outdoors overnight.

You can also use your popup greenhouse to help harden off plants. Open the air vents for a few hours a day to let cool air and breezes in. Gradually increase the amount of time that you open the vents. Work your way up to opening the side doors of the greenhouse, as well. This will provide your plants enough protection to create a microclimate within the greenhouse but will also get them ready to be grown outdoors without protection.