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Children love to help start seeds

How to start seeds indoors this winter

Children love to help start seeds

January marks the beginning of a new year and the beginning of a new gardening season. Sure, you could spend your winter sitting around in your pj’s watching movies as the cold season progresses, but being productive is so much better. Did you get your free seed catalogs in the mail yet? If not, there’s still time to order them. If you did get them, mark which plants you’re interested in growing this year and order seeds. If you already have your seeds, that’s fantastic. You’re ahead of the game already.

When do I start seeds indoors?

It all starts with knowing your frost dates. Right now, you’re looking for your annual average last frost date. This is an average of when the last spring frost is in your gardening zone. You want to make sure you plant vulnerable plants after the last frost or you could lose them and you’ll have to start all over.

Once you know when your last frost is expected, you can count backwards from that date to the date you should ideally start your seeds indoors. Most seed packets will say how many weeks before the last frost you should start them indoors. However, not all plants are suited for starting indoors. Rooted crops such as carrots are best directly sown in the ground or in containers. Most fruits and vegetables can be started indoors though. The seed packets will state if and when they should be started indoors or directly sown.

Start your seeds indoors early
How do I start seeds indoors?

To start seeds indoors, you need something to start them in such as seed starting trays, egg cartons or any container with individual cells and holes on the bottom for drainage. You’ll also need seed starting mix. You can purchase seed starting mix or you can make your own. To make quality seed starting mix use these components:

  • 1 part perlite
  • 1 part vermiculite
  • 2 parts peat moss
  • 4 parts compost
remove cover when seedlings emerge

You only need a small amount to start with in each cell.

  1. Place 3 seeds on top of the seed starting mix and press them down just slightly below the surface.
  2. Use a spray bottle rather than a watering can to provide moisture without disturbing the seeds.
  3. Then cover the tray with the lid it came with, or if you used an egg carton or other repurposed tray cover it with plastic wrap and poke a few holes in it for air circulation. Now you have a mini greenhouse.
  4. Make sure to check on it daily and keep the cells moist.
  5. Warmth is more important in the early stages than sun is. Place your seed tray on a warm surface. This could be on top of a refrigerator, near a radiator or wood stove, or you can purchase a seed starting heat mat.
  6. Once the plants sprout, it’s time to remove the lid or plastic wrap and place the tray in an area where it can get plenty of sun. A south facing window will offer maximum sun exposure. Seeds need a full day of sun. If you don’t have any south facing windows, or a space where the seed trays can get that much sun, you can purchase lights for them to grow under. One option is to hang fluorescent shop lights an inch or two above the seedlings and keep them on between 12 and 14 hours daily. You can also purchase grow lights online.

Seeds will germinate faster with warmth and young plants will grow faster with more light, but it is still possible for it all to happen simply placed in a sunny window. It just might take a lot longer.

remove cover when seedlings emerge
What seeds should I start indoors?

Plants that you want to harvest early on and those that take a long time to germinate should all be started now. Here are a few to consider:

  • Broccoli
  • Cabbage
  • Cauliflower
  • Celery
  • Head lettuce
  • Onions
  • Rosemary
  • Eggplant
When should I transfer the plants to the garden?

When plants first sprout they will have cotyledons, or seed leaves. These help seedlings with nutrients. The second set of leaves are known as true leaves. When the second set of leaves appear, you can move them to bigger containers and start preparing them for planting. It is important to acclimate plants before planting them. If you simply take them from the climate controlled environment they’ve always known to the unknown world outside, they aren’t as likely to thrive. They will suffer plant shock. It is important to harden off plants first.

To harden off plants, simply place them in a cold frame or outdoors in an area sheltered from the wind that receives good light. Leave them out there for a short period each day, increasing the amount of time they are out there every day for three to seven days.

That’s it. Now your wonderful young plants are ready to be transferred to your garden.

Have you started seeds indoors yet this year?

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