Hardening off plants before transplanting them into your garden is important.
By hardening off seedlings before transplanting them, you’ll reduce their stress.
You'll increase your chances of gardening success.
And maybe reduce your stress, too!
If you’ve started your seeds indoors, your little seedlings have no idea what’s in store for them in the cruel out-of-doors.
After all, you’ve pampered them from the beginning. You’ve seen to their every need. You’ve kept them warm, made sure that they had plenty of light, and never let them get thirsty or hungry.
You’ve not let them be attacked by insects or animals (unless your dog or cat got into trouble!).
Those little seedlings think that life is nothing but a bowl of cherries.
Wouldn’t it be cruel to just suddenly snatch them from their cozy, comfy life, and banish them to the hard outdoor world without any preparation?
Of course it would!
And you don’t want to be cruel to your seedlings, do you?
Of course not!
You love your little seedlings. That’s why you’re going demonstrate some tough love, and get them ready for their big transition. You’re going to give them some preparation, some training.
You’re going to put them through baby plant boot camp!
The objective of hardening off your seedlings is simply to get them acclimated to the rigors of outdoor life.
And the way to do that is to let them begin spending some time outdoors in a controlled, supervised setting.
Start by selecting a semi-sheltered outdoor area where you can place the seedlings. An ideal location will protect the plants from strong winds, hard rain, and direct sunlight.
You’ll start with only a couple of hours a day in this environment.
Each day, you’ll increase the amount of time outdoors. And you’ll gradually move the seedlings from filtered sunlight to full sun. Of course, you may not have locations that allow you to make such a controlled transition from filtered sun to full sun. Just approximate it as closely as you can. If you have some shade cloth on hand you can use that to help filter the sun.
You’ll also want to gradually increase the seedlings exposure to cold. How cold you’ll let them get depends upon the plant. Generally, warm season plants like tomatoes and peppers should not go below 60 degrees F. Cold season plants like broccoli and cabbage can be exposed to temperatures as low as 40 degrees F during the hardening off process.
You’ll also gradually decrease the frequency of waterings. But don’t let the seedlings dry out, of course.
After about a week of boot camp, your seedlings will be spending most of the day outside, and will be ready for transplanting.
It may be difficult to be as precise with your seedlings boot camp training as I’ve laid out. But just be sure not to expose the seedlings to too much, too soon. Any time spent acclimating to the outside world will be helpful.
Not at first.
In fact, the first time you removed your seedlings from the nice, cozy environment in which they’ve spent their entire lives, and carried them out into the scary outside world, they’d probably use language that would convey anything but gratitude!
But later, after they’d gone through the transplanting process and grown into fine, productive plants, they would understand (if plants could understand) that hardening off seedlings before transplanting seedlings is important. They would know that you did the right thing for them.
And you’ll know it, too.