While our friends on the West Coast may be enjoying an early spring, here in Iowa we’re still in the deep freeze with record snow cover. By mid-February, I’m ready for a break from the snow and cold. Most years I travel to a warm-weather destination for a few days to lift my spirits. That won’t happen this year. Instead, I just walk out the door of my basement and into the attached greenhouse. I took this shot of Vista Bubblegum petunias this morning when the temperature outdoors was in the teens.
Seeing the bright flowers in bloom is a great way to adjust my attitude. Gardeners are naturally optimistic–how else can you explain the leap of faith that it takes to plant seeds with the expectation of beautiful flowers or bountiful harvests of produce?
On sunny days the greenhouse truly is tropical. It often reaches 80 degrees even when temperatures outdoors remain below freezing. I love to open the basement door and allow the scents of springtime to fill the entire house. But overnight and on cloudy days, temperatures frequently dip into the 40s in the greenhouse, even with the triple wall acrylic covering and insulating bubble wrap.
In order to start seeds in the greenhouse, I have a germination chamber that keeps the seedlings warmer. This germination box is large enough to hold five standard nursery flats (plus a few extra plants). A heating mat supplies bottom heat, and maintains a constant 70 degrees F. The 8-inch deep box fell short for growing stem cuttings, so I added a 1-foot tall extension made of treated deck rails. Usually it’s draped with clear plastic, to hold in the heat. But the plastic rolls back to make it easier to water and work with the seedlings. This photo shows that the grassy onion seedlings are growing nicely, as are half a dozen types of perennial flower seedlings. I’ll soon start more annual flowers and veggies. By then the perennials will be able to move to the cooler greenhouse benches. And with improving weather conditions (I remain optimistic!) they’ll be ready to transplant to the garden when the snow finally melts.
If ever I needed proof that good potting mix matters to plants, I got it last weekend while repotting chestnut seedlings. These two seedlings were grown in the same size pot, in the same lighting conditions, and with the same watering and fertilizing regimen. Yet you can see the vast difference in root development. Plus, the chestnut on the right is substantially taller, as you’ll see in the photo below.
I remember what happened. I had run out of potting mix, so I substituted topsoil for a small number of seedlings. Even after “cutting” it with peat moss, the topsoil was too heavy and thick to be used as a container medium.
Moral of the story: use a good potting mix (here’s one I use) and beef it up with compost (and sand, if you’re working with woody plants). Avoid using topsoil in containers even if it’s amended. Your plants will be larger and stronger. And the more extensive root system will help plants deal with drought and neglect.