Starting Seeds Indoors
There are many reasons why it's smart to start seeds indoors:
- Many plants have long growing seasons and they won't flower or fruit unless they get a head start inside.
- Even if plants don't need to be started indoors, they'll grow larger and bloom longer if started early.
- Plants with fine seeds are protected them from harsh weather.
- You have a lot more control over weeds, insects, and disease.
- Of course, you can always buy plants in the spring from a nursery that started them indoors
Seed Selection and Preparation
Before planting, check to see if your type of seed needs any special handling.
Some seeds sprout easier if you soak them before planting. Don't soak them too long, however, because some seeds can become waterlogged and will decay.
Some seeds with hard outer shells will sprout faster if their shell is slightly broken. Use a knife, file or sandpaper to break the surface gently, without breaking the plant embryo inside.
A few annuals that must be started indoors include begonia, coleus, geranium, impatiens, some marigolds, petunia, pansy and verbena.
Some vegetables that need longer growing seasons in order to produce include broccoli, brussels sprouts, cabbage, cauliflower, celery, peppers, and tomatoes.
Start seeds about six to eight weeks before you expect to take them outside.
Containers and Soil
When starting seeds inside, it's important to have either a good, sunny window with a southern exposure or some cool-white fluorescent bulbs.
Plastic or wooden nursery flats will hold the most amount of seeds, but you can also use any kind of pot, foil pan, styrofoam or plastic cups, or milk cartons. Just make sure to punch holes in the bottoms for drainage.
There are also special seed starters that consist of pot and soil all in one.
If your container has held plants before, wash them thoroughly and let them dry in the sun to remove any fungi from previous plants.
If your container is made of peat or any absorbent material, you should soak it thoroughly before planting seeds so it won't pull moisture out of the soil later.
Using a commercial potting soil is your best bet, but you can also use your own mixture. One such mixture is one part good top soil, one part peat moss, and one part clean sand. You can also add vermiculite which will help keep the soil loose for the new roots.
Don't use garden soil because it can contain fungi and can cause your plants to rot.
Fill your containers to within 1/2" from the top of your container with your potting soil. Then level the surface with some type of flat board.
You can spread the seeds out evenly, or place them in the rows. Then press the seeds into the soil with a flat board.
Plant twice as many seeds as the number of plants you want because some of the seeds will not germinate, and some will be lost in transplanting.
Cover the seeds with soil, they should be buried to a depth of about four times their own diameter.
Tiny seeds will just need to be pressed into the soil lightly. Check your seed package for specific planting directions.
If your soil wasn't premoistened, set the container in water and let it draw it up water from the bottom. This method waters them a lot more evenly than top watering, and doesn't stir the seeds.
Mark each container so you don't forget what it is.
Next, place your trays or pots in clear plastic bags or cover them with plastic or glass. This will keep the humidity high so less watering is needed.
Keep the containers in a warm place, but not in direct sunlight.
Some seeds will require more light to germinate, and then you don't want to cover them. Check for specific instructions on the seed package.
Check the containers every couple of days to make sure it isn't drying out.
It'll take about a week for the seedlings to emerge from their shells and poke through the surface. Then you should uncover them and expose them to full sun or a grow light.
Keep the seedlings moist, but water them carefully so you don't drown or disrupt them. Watering from the bottom works best, however a fine mist sprayer works well too.
Acclimating and Transplanting Seedlings
Once the plants have grown two full sets of leaves, transplant them to individual pots to give them more room to grow and develop roots.
If your plants already have individual containers you won't need to transplant them.
Handle plants carefully when transplanting, and grab them by the leaves, not by the stem.
Some plants benefit from being pinched back. This helps them to be more bushy and colorful. This can also be used if your plants are getting too tall and you're not ready to plant them outdoors yet.
When it's warm enough to plant outside, set the plants outside for a few hours a day for a week and increase the amount of time each day. This will get them used to being outside.
When you're ready to transplant, water the plants and the ground where they'll be planted. It's best to plant on a cloudy day so the heat of the sun won't cause wilting.
Water your new transplants once a day for about a week until they are well established. If the plants start to wilt, cover them or give them shade until they revive.