After your seeds have germinated, and after they have their first two sets of true leaves and you’ve transplanted them into larger containers, you’ll start thinking about when to introduce them to the outdoors. The time to start acclimating them is two weeks before the date you’re planning to plant in your garden; in other words, two weeks before the time you anticipate the frost threat to be over. You’ll want to give your seedlings ample time to prepare for the harsher conditions of the outdoors before they’re planted in the ground, which is called hardening off. By the time the seedlings are planted in the garden, they should be able to endure fluctuations in sunlight, wind and temperature. Hardening off actually thickens the leaves of the plants which helps prevent shock.
We chose to allow two weeks to harden off our seedlings so that we can be flexible in the case of extreme outdoor temperatures. If we have a sudden cold day or two here and there, it won’t be a big deal if we’re delayed a few days when we have to leave the seedlings indoors. We’re hardening off seedlings as we speak. Here’s how:
- During the week before beginning to harden off outdoors, water the seedlings less often and stop fertilizing if applicable. If possible, you can also drop the temperature of the room a few degrees. These indoor hardening off steps aren’t necessary, but it doesn’t hurt to give the plants a little extra “toughening up” before they’re outdoors.
- On the first day, bring the plants outdoors to a shady, warm spot where they’re sheltered from wind. Leave them out for a few hours and bring them in. For the next few days, gradually increase their time in this same spot.
- After 4 days, move the plants from their shady spot into morning sun, then move them back into shade in the afternoon. Gradually increase their sun time an hour or two each day. Light wind is also good, but keep a close eye on the plants to make sure they don’t dry out. They should be watered every day or every other day. Remember to bring plants inside overnight.
- After 10 to 14 days of gradual sunlight increases, the plants should be able to endure a full day of sun and also be left out overnight as long as temps don’t drop below 40 degrees F.
The next and last post in my Starting Seeds Indoors series will be about planting the seedlings outdoors. Your seedlings have come so far, from seeds to baby seedlings to transplants to strong plants ready for the garden! It’s so satisfying to watch them grow with the hope that they’ll provide nourishment for you in the near future, in the form of delicious vegetables, herbs and fruits. Each plant is economically valuable, as you would spend at least $5 for a similar organically grown plant from a nursery. It’s possible to save even more money if you save seeds from this year’s plants to use for next year. If you have young kids, this process is priceless as it’s teaching them healthy living habits that can stay with them forever. Teaching my girls how to grow plants and healthy food, and seeing them get excited about it is probably the most rewarding part of gardening for me right now!
Are you transplanting seedlings into your garden soon? What are you growing?
Other posts in this series:
- How to Start Seeds Indoors
- Starting Seeds Indoors: What to Do When They Sprout
- Starting Seeds Indoors: How to Transplant Your Seedlings
- How to Give Seedling Plants a Strong Start in the Garden