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Five Mistakes Seed Sowers Make—Rose Marie Nichols-McGee Tells How to Get it Right


It’s indoor seed sowing time! Whether you set up a small table, or a full-size greenhouse, seed starting can sometimes be fraught with challenges. Just when you think your seedlings are growing well, they can turn up their toes.

It all comes down to the fungus among us, says Rose Marie Nichols-McGee, president of Nichols Garden Nursery in Oregon, and coauthor of The Bountiful Container. She says, “Your first priority is to prevent damping off and other diseases that can plague indoor growing.”

Here are five fungal mistakes and Rose Marie’s remedies that will bring you seed-starting success.

Mistake #1: Not cleaning equipment. You can buy fresh seed starter kits, but if your containers have been used before, Rose Marie suggests giving them a good scrub, and then a 20-minute soak in a 10 percent bleach solution. Rinse afterwards.

Mistake #2: Using the wrong planting mixture. “You want a sterile potting mix,” Rose Marie says, “Vermiculite or seed starting mix—not potting soil or dirt. It will say it’s for seeds on the bag.” Finely textured potting soil can be used later, when moving plants up to larger containers.

Mistake #3: Sowing too thickly. Rose Marie suggests that you practice sowing tiny seeds by cutting a small corner off the packet, and dispersing a few on a piece of paper. You can see how they fall. Further apart is better. For instance, she notes, “Basil can be planted half an inch to an inch apart.” If, despite your best efforts, bunches of seedlings emerge, thin with nail scissors so you won’t disturb the roots of those you want to keep.

Mistake #4: Watering too much. Finding the right balance for water delivery is about weight. Lift trays to learn what they feel like when wet and dry. “If you touch the soil surface with your finger each day and it’s always wet—you’re overwatering,” Rose Marie says.  She favors hose nozzles called Fogg-it. “I swear by those. I used them as a child and they still make them. You’ll never overwater.

Mistake #5: Failing to provide enough air circulation. “The warmer your greenhouse, the more you’ll want to keep air moving,” says Rose Marie. “Even a tiny fan near your seedlings helps them to form sturdier stems and controls fungal issues.” She also advises that you provide generous spaces between all your greenhouse plants so that air can flow freely around them.