Name: Paul Utah (Zone 5b) Grandchildren are my greatest joy.
I've used them in March here. Occasionally had ice in the tubes and had them under snow and the plants were fine. Sometimes the the tomatoes grow out of the top and the top of the plant freezes but the plant still continues to grow,
The calendar date depends on your climate. I use mine to start tomatoes about 4 weeks before my average last frost date.Go into the "Goodies" section and pick the Garden Planting Calendar. Enter your zip code for the average last frost. The four weeks give me a good headstart and the tomatoes are just growing out the top by the time all danger of frost is past. I can take the water walls off the plants and the tomatoes really take off.
