| I planted zonal geranium seeds (orbit series) Feb. 1 and placed them in the greenhouse. They are getting plenty of water and fertilizer but the seedlings turn yellow and eventually are slightly stunted (this happened to the seedlings I planted last year as well). Once planted in the ground in May they do just fine after 2 weeks and turn into beautifully blooming plants. I suspected last year the pots were too deep and drainage was a problem. This year I used shallower pots but the problem is still occurring. |
| More than likely, the problem can be traced to excessive humidity or air temperature within your greenhouse setting. Geranium seeds require moisture and 70F for best germination. After sprouting, the temperature should be reduced to between 62F and 65F during the day and 58F-60F at night. Supplemental lighting should be provided 12-14 hours each day. Soil pH is important to geraniums, as well. If you're using a basic peat mix, you may need to add lime to neutralize the pH. Do a soil check and adjust to 6.5 to keep your geraniums as healthy as possible. Hope the above provides some insight into the perfect growing conditions for your seedlings. |
