WHY YOU SHOULD GROW PLANTS FROM SEEDS
While some women covet shoes, I go weak in the knees for a new packet of seeds. Each seed package offers the promise of a flower more beautiful than you’ve ever imagined or a vegetable so delicious yet disease resistant. Growing plants from seeds offers you the chance to grow unique varieties and lush plantings of flowers, herbs and vegetables. Plus growing seeds indoors offers avid gardeners the chance to get a head start on the growing season.
WHEN TO SOW
If you start seeds indoors around late Feb-March-April, your seedlings will be ready to set outdoors around mid to late April-May depending on where you live, once evening temperatures settle in around 55 degrees for about a week straight. If it’s getting to be late spring or even early to mid-summer, don’t bother with sowing seeds indoors as it’s easier to sow them directly outside. Don’t feel bad if you waited so long. The plants will be germinate quickly. I find plants that are sown directly outside are hardy, less susceptible to disease and are generally sturdy plants. Seeds like zinnias and sunflowers are best sown directly outdoors from mid April through early June.
CHECK THE WEATHER IN YOUR AREA
It’s best to check the weather history in your area. Go to weather.com and enter your zip code. On the forecast screen, click on the yellow “Averages” tab. The blue dots indicate average lows but keep in mind these are only averages and certain years get hit by either unexpected freezes or an early warming trend. It seemswith global warming, areas are hit by unusual weather extremes by on the whole, I’ve noticed in my area of Washington, D.C. spring keeps edging forward earlier each year.
IF YOU’RE STILL NOT SURE
If you’re still uncertain about weather in your area, stop by your local garden center to ask for advice or check with your local state’s cooperative extension service. In some areas such as Washington, D.C where it’s a long growing season, it’s best to err on the side of starting later than to be stuck with a tray of leggy plants.
CHECK THE SEED PACKAGE FOR HOW LONG IT WILL TAKE THE PLANT TO GROW
Most seed packages will tell you the plant’s preference to be sown directly outside or not, sun requirements, how tall the plant will get, the number of days to germinate and days to harvest. In high humidity areas, look for “mildew-resistant” varieties for plants that are susceptible to white powdery mildew disease such as zinnias, cucumbers and zucchini. Make sure in particular you follow the directions on how far to space the seeds apart. On tomatoes, “determinate” means the tomato will grow to a pre-determined height of two to four feet then flower, fruit and stop producing fruit. “Indeterminate” varieties continue to grow until the end of the season.
WHAT DO I PLANT THEM IN BIGGER POTS?
Seed starting kits will include a plastic tray and either plastic cell packs or jiffy pots and pellets. Be sure to get one with a humidity dome to keep your seedlings warm and moist. A standard kit is about a foot wide and less than two feet long while other more narrow windowsill versions are also available. On standard kits you can choose from 24 to 72 individual cells. The larger number of cells allows you to grow more plants but it’s likely you’ll have to transplant plants earlier because of the limited growing space. You can reuse plastic trays while jiffy pots and peat pots allow minimal root disturbance as transplants can be planted directly into the garden.
CAN’T I JUST USE ANY OLD DIRT?
Use potting mix and preferably a seed starting mix. Avoid previously used potting soil and select a lightweight seed mix comprised of sphagnum peat moss and perlite or vermiculite to allow seedlings the moisture and oxygen they need. Seedlings are susceptible to diseases such as “damping-off” fungi. Before you use your garden trowel to scoop out any seed mix, be sure to clean off and rinse with a watered down solution of bleach.
PREPARING THE SOIL
Prepare the soil for planting by using a spray mist bottle to wet the soil until moist. Plant about 1-3 seeds per cell and use plastic markers to indicate the date and what you’ve planted. Place the plastic humidity dome lid on top of the seed tray to retain moisture and warmth. With any extra seeds, tape up the package and put the rest in a fridge in a zip lock bag to sow directly in the garden in case the seeds do not germinate.
WARMTH IS CRITICAL FOR GERMINATION
The most important thing seeds need at first is heat. Avoid placing your seeds on a drafty cold windowsill. Place your seed tray on top of a fridge or water heater where it can get bottom heat of about 70 to 85 degrees. Otherwise, try a seedling heat mat such as one made by Hydrofarm which warms the rooting area to improve germination and rooting. It’s made exactly the size to fit under a standard seed starting kit.
PROVIDE ADEQUATE SUNLIGHT
Depending on the seed, you should start seeing seedlings in about a week or two. Once the seedlings emerge they’ll need light and ventilation. At this point, the heat mat is no longer necessary and the seedlings should be placed in a south-facing windowsill. If your home does not have these ideal growing conditions so you can place the seedlings under an inexpensive fluorescent shop light with two 40 watt cool white lights. Suspend the shop light on chains and use “S” hooks to raise the lights as the plants grow, keeping them about 2 inches above the plants. Keep the lights on about 16 hours a day.
The first leaves to emerge will be small rounded baby leaves followed by sets of true leaves which will resemble the mature plant leaves. At this point you will want to begin gently watering. Once the seedlings are about two inches or so, give them more growing room by repotting into larger containers. Begin a weekly feeding of half strength fish emulsion or liquid fertilizer.
Once temperatures outside have warmed to at least 55 degrees at night, take the next week to harden off your seedlings. Start with half a day in the shade then gradually increase the amount of time. By mid to end of the week, start with half a day in the sun and gradually increase the amount of time until the seedlings have been left out all night. It is recommended the hardened off plants then be planted in the garden on an overcast or cloudy afternoon to minimize further stress.
If it sounds like too much effort to start seeds indoors, try to limit the number of plants you start indoors so you don’t get overwhelmed with too many plants and too little space. If things don’t work out, don’t worry, you can always plant seeds directly outdoors. It’s so worth the effort and extremely gratifying to grow things from scratch. You will save on plant costs and it makes counting down the days to spring go so much faster.
ABOUT THE AUTHOR
Adrienne Jenkins has been gardening her entire life since her Dad taught her everything she needed to know about plants. She is grateful her father shared his love of seeds and has fond memories of carefully selecting a papery thin package of godetia seeds and being delighted when they sprung from the ground looking like those bright flowers pulled from a magician’s hat. Adrienne wrote a regular monthly column for “The Hill Rag”, a community newspaper in Washington, D.C. and was the garden center manager for the historic Frager’s Hardware on Capitol Hill.