Once your seeds have germinated and had a chance to grow a bit, it is time to thin your seedlings to one per pot.
|Day Seven: Before Thinning|
Pick strongest seedling in each pot and use a pair of scissors to snip off all of the other seedlings. It can feel almost painful to cut healthy little seedlings, but I assure you that it is very important. You want to give the remaining seedling all the space, light, water, and nutrients so that it will grow big and strong. We fed our thinned seedlings to our rabbits, which helped ease the pain a bit. Happy bunnies will cheer anyone up!
Tip #9: Thin your seedlings to an appropriate spacing.
As the seedlings grow taller, keep an eye on the distance they are from your lights. You will have to move the lights up to maintain a 1-2" distance between the plants and the light. Don't forget to keep the soil moist, but not sodden, as well.
Tip #10: Check on your seedlings daily to monitor light and moisture levels.
One extra thing you might consider doing is to set a fan blowing gently over the seedlings. This will help to strengthen their stems so they will be able to better withstand the elements when they get transplanted outdoors. Or, if you really want to be hands-on, you can softly run your fingers over the tops of the seedlings for one minute, two times per day. This supposedly will have much the same effect.
Tip #11: Strengthen those stems by running a fan.
This is the sight that greeted me on my daily checkup seventeen days after sowing our cabbage, kale, and broccoli seeds.
|'Farao' cabbage seedlings|
|'Dwarf Blue Curled' Kale|
|'Waltham 29 Broccoli'|
All the seedlings were doing well, but we noticed that it was time to transplant the ones growing in the tiny toilet paper roll pots.
|We moved the seedlings from the toilet paper roll pots into larger containers.|
The toilet paper roll pots work fine, but they do dry out more quickly than the plastic pots we made from recycled materials (pop bottles, milk jugs, etc.) and they only hold a tiny amount of soil. Rapidly growing plants need a bit more room.
It can be a bit tricky to transplant such tiny seedlings without harming them, but if you remember to only handle the seedling by the seed leaves (NOT the stem!), you will avoid damaging the plants.
Tip #12: Transplant as necessary. Handle only by the seed leaves, not the stem.
At this time, you should consider fertilizing your seedlings. The seed starting mix we are using is fortified with fish meal and provides enough nutrients for plants to make it to the transplant stage without additional fertilization. Many seed starting mixes are essentially void of nutrients, however, so you will need to fertilize. Use a gentle fertilizer like liquid kelp diluted in water and fertilize about once a week during one of your routine waterings. You can even make your own organic liquid fertilizers for free if you so desire.
Tip #13: Fertilize with liquid fertilizers once plants have true leaves.
Keep caring for your seedlings like this until it is time to transplant them outdoors. Before you throw them out in your garden, however, you need to first harden them off.
|See what a difference a decent light rig makes? Last year's transplants were super leggy, but at |
least I hardened them off properly! Here they are hardening off on a shady porch
between a rosemary plant I overwintered indoors and a blueberry bush.
Hardening off is the process by which plants get acclimated to the outdoors. Start by placing a tray of seedlings in a shady area outdoors for a couple of hours. Gradually build up the time the plants spend outdoors and the amount of sunlight the plants are exposed to over a week or so. This is an essential step for happy plants that survive their final transplanting into the garden.
Tip #14: Don't forget to harden off the plants.
That's it! Now you have all you need to know to grow healthy plants from seed indoors. Happy gardening!