Zinnia Seedling Leaves Have Light Spots And Some Have Curled
Question From: R. Standish - Elbridge, New York, United States
Q: Hi. I have started zinnias from seed and this is my first time. The majority of them are really healthy. I'm started them in the jiffy seed starting mix and trays and once the first true leaves appeared, I transplanted them into 4" pots and used the Miracle Grow Moisture control potting soil. I am careful to water them without getting the leaves wet. I have a cold frame which is heated with infrared heat lamps which started at 65 -72 and I have dropped the thermostat to 55-65. I also have small fans running. The box is 72" by 36" and 12" in the front, 18" in the back, covered with old windows and gets full sun pretty much all day. I have recently noticed that a couple of them have light spots on the leaves. I thought maybe it was from cold water that dripped on them from condensation on the Windows, but I'm not sure. I did recently add a few grains of miracle grow flower plant food to my soda bottles I use for watering (with tiny sprinklers on them). I water with warm tap water which is public water. Can you help me figure out what this is and how I could be sure I don't lose them all? Some of the leaves are curled a bit as well!! Yikes! Thanks for your help!
*I think the issue is cold soil and possibly air temperatures. The soil should be a minimum of 60 degrees and the nighttime air no colder than 50 degrees. Just because your thermostat is set at 55 does not mean it does not get colder in the cold frame. It just means the heater runs continually when the temp drops below the setting. Get a maximum minimum thermometer at Amazon.com, Home Depot or Lowes and soil thermometer. Don't water them in the evening. Good Luck Nancy