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Common Seed-Starting Mistakes

Seeds are like magic to gardeners and one of the miracles of nature.  Plant them in soil, keep them moist and you're on the way to a beautiful bloom or bountiful harvest.  Or, you can start seeds indoors to jump-start your garden with new or unusual varieties. Whether you have started plants from seeds before or have never had the pleasure, you'll improve your success by avoiding these common mistakes.

Mistake #1: Getting Hypnotized By Catalogs

It's tough to resist the glorious pictures and glowing words in mail order seed catalogs and on websites, especially if the ground is covered with snow outside. Even many an experienced gardener has succumb to the allure of the beautiful pages. So, try to avoid the first mistake most seed starters make: ordering way too many seeds. Be practical and exercise self-restraint. If you're a first-timer, don't start with too many different types of seeds. Stick with the ones that are easy to germinate and grow, such as Tomato, Basil, Zinnia, Sunflower or Cosmos.

Mistake #2: Starting Too Early

In many cold-winter regions, sowing seeds gives you a chance to get your hands dirty when it's too cold to plant or garden outdoors. So, hold you horses and avoid failure - don't start your seeds too soon. Most plants are ready to transplant outside in 4-8 weeks after germination. 

Mistake #3: Planting Seeds Too Deep

Check seed packets carefully, for specific information about how deep to plant seeds. A general rule of thumb is to plant seeds at a depth equal to two or three times their width, but it's better to plant seeds too shallow than too deep. Seeds of some plants, such as certain Lettuces or Snapdragon, need light to trigger germination and shouldn't be covered at all. Such seeds, however, should be lightly tamped after sowing so they have good contact with the soil.

Mistake #4: Not Labeling Properly

Make labels before you sow any seeds.  Nurseries, mail order catalogs and garden websites sell a variety of types from wooden to metal. Use a water proof pen. Place the labels in the appropriate pot, flat or six-pack immediately after sowing, making sure there will be no confusion.  Otherwise, it will be tough to tell the different seedlings apart and what they are supposed to mature into. You should also include sowing dates on your labels so you know when to expect germination.

Mistake #5: Soil Is Too Cool

Seed packets specify the soil temperature seeds require for the highest percentage of germination. Remember, that’s soil temperature, not air temperature. Most seed germinate at around 78ºF but it can vary. You can increase your chances of success if you use a waterproof root-zone heating mat. After germination, aim to keep soil temperature in the 65-70ºF range.

Mistake #6: Not enough Light

In mild winter regions of the country, there's enough ambient light in a south-facing window in winter to grow stocky seedlings. In more northern areas, you'll probably need supplemental lights. You can buy or build light stands to start seedlings.  Nurseries, mail order catalogs and gardening websites offer a wide variety for purchase. For stocky, healthy seedlings, provide 14-16 hours of light per day. Suspend the lights about 2-3 inches above seedlings or follow the directions on purchased kits. 

Mistake #7: Watering Woes

Keep the soil damp but not too wet.  One helpful option is to cover the container with clear plastic or other material to keep soil moist until seeds germinate. Once seeds sprout, don't miss a watering or your seedlings will almost surely die.  Unlike established plants, seedlings don't have an extensive root system to rely on for water. At the same time, it's important not to overwater and let seedlings sit in soggy soil, which encourages disease. 

Mistake #8: Not Enough Pampering

Newly germinated seedlings are delicate creatures. They need to be checked daily and given lots of tender loving care, especially early on. If you can't monitor seedlings daily, checking on germination, soil moisture, temperature, and lights, you'll reduce your chances of success significantly. It’s a hard lesson to learn that seedlings don't survive neglect.