Grow Seeds Inside Successfully
It’s easy to raise flowers and vegetables from seed successfully inside where you can control growing conditions if you follow a few simple guidelines. Why should you go to the trouble? Because you can get many more varieties of plants from seed racks in garden supply stores or from mail order catalogs than you can directly from nurseries.
For the price of one plant you can get several packets of seeds, and then you can raise as many plants of the variety as you want. Besides, and most important to a serious gardener, you get the fun, excitement, and challenge of gardening inside months ahead of when you can venture outside (and the weather is better inside.) Here’s what you need:
Sterile growing medium for germinating seeds (optional)
Sterile potting soil (necessary)
A surface over which you can set up lighting
One or more fluorescent shop lights
A timer (optional, but I think it’s essential)
Electric soil heating cable for faster germination (optional)
Cleanliness is essential
The first tip for successful indoor planting is cleanliness, so that disease organisms don’t murder your seedlings. Wash your hands, the surfaces on which you work, and any utensils, containers, etc. that you will use. I sterilize anything that is being reused in a solution of one part bleach to 10 parts warm water. I wear rubber gloves and my oldest clothes including shoes, because I learned the hard way that bleach water wrecks havoc on everything it touches, including skin. I air-dry the containers to prevent recontaminating them.
You can use almost any containers to germinate your seeds: shallow flowerpots, margarine tubs (without the margarine in them,) plastic containers with clear lids you get from baked goods or take-out salads, etc. (At last, a use for all those containers you’ve been saving because you were sure they’d come in handy some time.)
To germinate seeds I’ve found it most convenient to use 9 x 12-in. plant trays in which I sow five or six rows of seeds with the same needs for temperature and time to germinate. After seedlings appear you can transplant them into peat pellets, peat pots, foam cups, trays, or three- or four-in. square- or round plastic pots.
I use homemade newspaper pots (more in another article.) I put these into 12 x 22-in. mini-greenhouse trays with clear plastic lids that you can buy in garden supply stores and catalogs. They’re a good investment because they last for many years.
Seed packets give instructions you must follow to the letter. Some seeds require darkness to germinate, some prefer chilling or even freezing, and some won’t come alive for eons unless you nick the ends with nail clippers or rough them up by rubbing them on sandpaper. Some must be surface-sown, and you just press these into the potting soil to ensure good contact. (There’s the personal touch… with clean hands, of course.)
I always water the potting soil thoroughly, then put in the labels, sow the seeds sparsely, cover seeds that require it to the depth the package calls for, and mist the surface to settle them in.
I cover the plant trays with plastic or put them in sealable plastic bags, and place them in warmth, if that is what the seeds prefer. You can buy a soil heating cable if you grow many seeds that prefer 70 degrees or higher to germinate. The fluorescent lights do raise the temperature a little because I keep them only a few inches above the trays.
Never use ordinary soil for your indoor growing efforts. Even if you sterilize it by baking it (which smells up your house horribly,) it is too heavy and it can still contain microorganisms and weed seeds. (Last year I bought bargain potting mix that was supposedly sterile, but it obviously contained stinging nettle seeds. Those suckers stung me for hours after I weeded them out of the soil. Talk about malicious plants! Needless to say, I’ve crossed that brand off my gardening list.)
If you don’t want to get more than one growing medium you can use your sterile potting soil to start seeds. I use vermiculite to germinate my seeds, then transplant seedlings into a sterile soil-free potting mix that contains fertilizer which feeds plants for six months. This saves the time and work of fertilizing with one-half strength liquid fertilizer every two weeks, inside and monthly outside.
You can use Popsicle sticks craft stores carry, or plastic labels of various sizes and colors from garden supply outlets. I often raise the same plants in successive years, so I buy indelible marking pens to write on them. For germination labels I write the depth the seeds prefer, temperature they need to germinate, and the time it takes. For planting labels I put the name, color, height, and amount of sun they prefer.
You could grow seeds on a sunny windowsill, but many vegetables have been cooked prematurely this way, because the sun heats them up disastrously under a plastic cover, or dries them up in a twinkling without a cover. Also, early spring sunlight is too scanty to grow the seedlings into robust plants. (They often develop giraffe-necks as they strive for more light.) It is better to create your own greenhouse effect (the good kind) with artificial light because you can control it. Your seedlings can wait for real sunlight until they get outside.
I raise my seeds under four-foot long fluorescent shop lights connected to a timer set to give 14 hours of light per day. (You don’t need “grow light” bulbs.) I suspend the lights on chains a few inches above the seedbeds until germination takes place, then I raise them above the seedling level as needed. (Another article will tell about how you can make your own fluorescent-lighted plant stand out of PVC pipe and plywood.)
Transplanting and watering
Some writers suggest waiting until seedlings grow one or two sets of true leaves, but I transplant as soon as I can handle them to lessen root injury and transplant shock. I plant them gently without pressing them in, letting a fine misting of warm water settle them afterward. It doesn’t hurt to tell them how good they look and how much you look forward to seeing them grow tall and strong. (Call me a nut, but my whimsy does seem to work. Like all babies, seedlings thrive on a nice dose of TLC.)
After planting the seedlings into pots, I put them in the mini-greenhouse trays and bottom-water them when the growing medium feels dry to the touch, usually every four to seven days. Bottom watering avoids troubles such as damping off and fungus gnats. It also carries the nutrients from time-release fertilizer granules in the potting soil up to where they’ll do the most good. I set out gallon bottles of water to warm up to room temperature because no one likes the shock of cold water on their roots. (Stick your toes in ice water if you don’t believe me.)
Hardening off and planting outside
You’ll soon have healthy, flourishing seedlings that are raring to grow outside. When the weather has settled and the daytime temperature rises to about 60 degrees, usually the end of May here in Zone 6, I “harden off” my plants for about two weeks. That is, I put them outside during the day for gradually longer times to acclimatize them to sun, wind, and cooler temperatures. I bring them inside at night and any time that cold, heavy wind, or a pounding rainstorm threatens.
I’ve found an easy way to get them in and out. I put the 11 x 22-in. greenhouse trays crosswise on two child’s red wagons and wheel them in and out of my garage. (Sometimes you can find these handy garden helpers at yard sales or thrift shops.) During this two weeks my husband parks his car at the curb. He’s very tolerant of my gardening needs and I’m sure there’s a special place in heaven for such saints.
Then when deeper green leaves signal the plants are ready, I transplant my leafy children outside on a cloudy day or in the late afternoon. (If you use peat pots, crumble the bottoms as you plant because some roots find it hard to break through them.) Give seedlings extra attention until you see new growth.
Growing your own seedlings is intensely rewarding, both in saving money and in satisfaction. You aren’t at the mercy of a limited selection of varieties, and you have the fun of gardening a couple of extra months, in controlled conditions, reveling in the thought that your garden is really your very own, from the seed up.
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