Before I can transplant all of the plants I started indoors, I will have to harden them off. Hardening off plants is basically acclimating plants that you started indoors to the outside weather. It allows your plants to get used to the sun, wind, rain, etc. gradually–kind of like slowly allowing your kids to experience some of life’s harsh realities {only plants won’t eat all of your food and make your house smell like dirty socks}.
I usually harden off my plants for about seven days, but some people shoot for closer to two weeks. I have milder weather here, so it is a bit easier to get them used to the outside. About a week before you plan to harden off your plants, you need to stop fertilizing them {if you use fertilizer} and scale back on the water.
Start the process by leaving plants in a shady spot outside for a couple hours–but make sure to bring them in at night {my favorite spot is my front porch}. Each day, gradually increase the amount of time you leave your plants outdoors, as well as how much direct sunlight they are exposed to. After about 7 days, your plants should be ready to stay out all day and all night {make sure to check temperature requirements for each plant to make sure it is staying warm enough at night}.
Once you have hardened off your plants, you can transplant them into the garden. If possible, try to transplant them on a cloudy day {pretty much always possible in my neck of the woods} and water them in well.
That’s it, it’s like the final step before the actual gardening starts. Weeee!
~Mavis
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Dale Ann says
Love your how to’s with the wonderful images to go with!
One more little trick I found in transplanting both plants, bushes, and trees…
After multiple side by side tests of transplanting before noon and transplanting late afternoon… I found transplanting (or repotting) them in the late afternoon gives me almost double the success in their survival and acclimation.
Kerry C says
A friend of mine and I were wonder about starting seeds indoors. Our plants get a little spindly before its time to plant them outside. How do you prevent this? Mine usually die not long after they become spindly and I end up buying plants.
Mavis says
Where are you growing the seeds and how much sunlight are they getting? If I had to guess they need more direct sunlight.
Kerry C says
Thanks for your help. I’m in Southern Idaho. I have them growing in a spare room with a south facing window. I will see what I can do to get them more sunlight.
Francisca says
I need to start hardening mine off too and was just wondering about this so great timing. Can I move them into the greenhouse and harden off there? Or is it better to move them back into the house at night? I am in Port Angeles and our nights have been in the high 30’s. My greenhouse is not heated. What do you suggest? And thanks again for your time and advice!
Cecily says
Hi Francisca,
I live in Tacoma and start my plants in my greenhouse. It is heated and I also use grow lights and heat mats. About a month before setting out I turn off the heat and two weeks later I turn off the heat mats. Ten days before the plants go out I open the widow vents and leave them open 24 hours. During the last 3 days I bring them outside and gradually acclimate them to direct sunlight. I’ve had great success with this method and I’m sure you can put your plants out in your greenhouse after the first of the month.
Jennifer says
What kind of fertilizer do you recommend?
Francisca says
Cecily thanks so much!
Dora says
When you have so many trays of seedlings to harden off, do you tend to do them in cycles? Like basil and cucumbers today, lemon grass and tomatoes tomorrow and lavender and leather (for Judy collins fans) the following day? Seems pretty laborious to put them ALL out then bring them ALL back in….? What do you do?
Mavis Butterfield says
Good question! Once you start to harden them off, you need to be consistent. So if you have a ton then I would suggest starting with as many as you can set out in a day and harden those off for 5-10 days them move on to the next set. 🙂
Michelle says
My question isn’t quite about this, but didn’t know where to ask. I started my seeds. I now have sprouts. I am a newbie to starting from seed. I read I should now take the green house tops off. But, some of them are shooting roots thru the peat pods. Do I need to transplant them fir them to survive? I am not supposed to transplant outside until mid may. They said 10 weeks prior. Are they ok, or should I switch to a larger pot?