Thank you for your question about stalled seedlings. It sounds like you are growing your plants under ideal conditions, so the lack of true leaves is indeed puzzling. Below you will find a few contradictory suggestions but by no means a full answer. In fact, the problem may boil down to a subtle interplay between light, watering and temperature. It occurs to me that the temperature of the water or the time of day in which the watering takes place may be influencing the growth of the plants. According to an Ed Hume’s Garden Questions Archives article entitled, Starting Vegetable Seeds Indoors, seedlings should be watered with water that is just a little warmer than room temperature.

If the water being used is too cold or if watering occurs in the evening as the temperature of the room drops, this could be slowing the plant growth.

Here is another pearl of wisdom about seedlings that may or may not contradict the above. I include this because I am wondering if the day time temperatures are too high. To quote from The Seed Starter\'s Handbook: Plants grown indoors in warm rooms put on weak, spindly, sappy growth that is difficult to manage… Start seeds warm and grow seedlings cool.
Source: The Seed Starter’s Handbook by Nancy Bubel. 1978. p. 49.

Lastly, Starting from Seed says: Since both heat and light fuel plant growth, the relationship between the two is critical. A common mistake among home gardeners is to keep plants at too high a temperature for the amount of light they receive. What often happens is that the gardener tries to compensate for slow growth with more fertilizer and higher temperatures. The result is limp, leggy seedlings that are hard put to cope with outdoor conditions… On cloudy days, the experienced gardener lowers the temperature to compensate for the lower light levels. While every plant has a temperature range it likes best, within that range, the cooler you keep the temperature, the better off the plant will be. Do not take things too far, though. A combination of low temperature, low light and overwatering is ideal for the development of damping-off fungus.
Source: Starting from Seed: The Natural Gardener\'s Guide to Propagating Plants. Brooklyn Botanic Garden. 1998, p. 71-72.

Season All Season
Date 2008-01-24
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