-
Step 1
Hardening off is a process that takes about 10 days, so plan ahead and start the process in advance of when you want to plant your seedlings. If you are planting seedlings that will be damaged if exposed to frost (like tomatoes or zinnias), be sure that the hardening off process ends after your average last frost date in spring.
-
Step 2
On the first day of hardening off bring the plants outdoors during the warmest part of the day and place them in a sheltered shady spot. Leave them outside for 2 hours and then bring them back indoors.
-
Step 3
The next day, bring the plants outside and place them in the same spot, leaving them for 3 hours. Repeat this process for two more days, until they have been left outside for a total of 5 hours.
-
Step 4
On the fifth day, bring the plants outdoors and place them in a sheltered, sunny spot. Leave them out for 4 hours (be sure to water them well before bringing them outdoors, as they will dry out more quickly in the sun). Repeat this process for two more days, leaving them out for a total of 8 hours on the seventh day .
-
Step 5
On the eighth day, bring the plants outdoors and place them in a spot similar to their final outside home. Leave them out for 8 hours. The next day leave them out the entire day. Finish the hardening off process on the tenth day by leaving the plants outside for an entire day and night (as long as frost is not predicted). Then they’re ready to plant!
