So you’ve put your passion, patience and hard work into starting your seeds, and watching them grow into young transplants. Now, it gets interesting. If you were to take your transplants and put them directly outside, there is a good chance that many of them will be damaged or even killed. Why? Because the change in environments was too great.
Hardening off is the process of preparing seedlings to handle the conditions of outdoor life. Think about it. While your seedlings were inside, they were in an almost perfect world. No wind, bugs, diseases, rough soil, pets, critters and lawn equipment. They got watered when they needed it and for the most part, got the light they needed. This perfect world isn’t exactly a good thing.
So how do you harden off your seedlings? By first starting to simulate outdoor conditions while still inside, and then gradually getting them used to outdoor conditions. Brushing your hand across the seedlings on a daily basis, or even using a hairdryer, can simulate “wind”. Then, there is the adjustment period where you expose them to more sunlight, wind and real watering (in other words, using your regular watering tools).
I have come up with a suggested transition “schedule”, which is what I’ve used the last 3-4 years. By no means is this set in stone, and quite honestly, is erring on the side of safe. I realize that not everyone has the luxury of being able to be at home for several days in a row. This is why I would recommend starting the transition right before a weekend. Your transplants may be fine after 3 or 4 days of transitioning, which is great.
First 1-2 days:
• NO direct sun exposure
• Protect from all wind if possible
• Bring inside overnight
Next 2-3 days:
• Direct sun for only 1-2 hours
• Moderate wind protection
• Leave in garage or cooler location overnight
Last 2-3 days:
• Direct sun for 3-4 hours (more if they are responding well)
• No wind protection
• Leave outside overnight if there isn’t a frost/freeze threat