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Search Results for: Seedlings | Catalog search for: Seedlings

PAL Questions: 2 - Garden Tools: 1

Keywords: Antirrhinum, Capsicum, Vegetable seedlings, Seedlings, Tomatoes

PAL Question:

I started some seedlings of tomato, pepper, snapdragon and lettuce in my sunroom under shop lights in peat pots. The temperature in the room is in the 60s at night and 70-80 in the day. I keep the soil evenly moist, but after 3 weeks, none of the seedlings that have germinated have true leaves. No secondary leaves of any kind. I cannot imagine why this would be under those conditions. Can you help me?


There are a number of variables that may be at work here. Are the seeds new? If not, were they stored properly? Also, seeds have varying lifespans. Some seeds require light to germinate and others do not. Some must be sown on or near the surface, and others must be sown more deeply. Seeds require varying degrees of heat. Oxygen is another requirement: is the seed-sowing mixture in your pots compacted? That might prevent germination. The steady moisture you are providing is good, and the temperature in the room is about right for most seeds.

University of New Hampshire Extension has useful general guidelines for starting seeds indoors.

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.

I am wondering if the day time temperatures are too high. To quote from The Seed Starter's Handbook by Nancy Bubel (Rodale Press, 1988): "Plants grown indoors in warm rooms put on weak, spindly, sappy growth that is difficult to manage. Start seeds warm and grow seedlings cool."

Lastly, Starting from Seed by Karan Davis Cutler (Brooklyn Botanic Garden, 1998) 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."

Season All Season
Date 2017-01-06
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Keywords: Plant identification, Seedlings

PAL Question:

I have some seedlings coming up in my compost. They smell a bit like basil, but they could just as easily be weeds. I'd like to know if there are resources for identifying plants at this early stage of growth.


You could wait a week or two and allow the seedlings to develop, which might make identification a little easier. However, there are various resources online for identifying plants, especially weeds, at the cotyledon (seed leaf) stage.

There are also print resources which illustrate plants at the seedling stage:

  • Seeds of Woody Plants in North America by James A. and Cheryl G. Young (Dioscorides Press, 1992)
  • Woody Plant Seed Manual prepared by the Forest Service, USDA (1948), also available online
  • Seeds: The Ultimate Guide to Growing Vegetables, Herbs & Flowers by Sam Bittman (Bantam Books, 1989)
  • Park's Success with Seeds by Ann Reilly (Geo. W. Park Seed Co., 1978)
  • Park's Success with Herbs by Gertrude Foster and Rosemary Louden (Geo. W. Park Seed Co., 1980)
  • Weeds of the West edited by Tom Whitson (Western Society of Weed Science, 2000)
  • Weeds of California and Other Western States by Joseph DiTomaso and Evelyn Healy (University of California, 2007)

Season All Season
Date 2016-12-23
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Keywords: Seedlings, Indoor gardening, Seeds

Garden Tool:

Seed racks are sprouting up at nurseries and grocery stores across the city - it's time to start seeds. One reason to start your own transplants is to save money. One packet of 50 marigold seeds typically costs the same as one 4" little start. The budget growing may extend into seed growing supplies by using recycled plastic pots from last season or even reusing individual yogurt containers or other comparable containers. "Growing chambers" can be made on the cheap from clear plastic bags and chop sticks to keep the moist plastic off emerging sprouts. The frugal gardener will be tempted to put those seedlings in a south facing window, but beware: Pacific Northwest windows are NOT bright enough to produce healthy, sturdy seedlings.

Invest in a 4 foot fluorescent shop light from the hardware store. It is worth the small amount of money. Buy one 40 watt cool tube and one warm tube, or if you're feeling extravagant buy the full spectrum grow lights, which will cost more. These lights should be replaced every year or at least every two years. Once your seedlings are up, the lights should be about 2 - 4 inches above the leaves. This can be tricky if you have plants growing at different rates. Try placing a platform under the short seedlings.
For a full explanation of fluorescent lights for seedlings go online to: http://www.garden.org/articles/articles.php?q=show&id=817

Season: Spring
Date: 2007-04-03
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March 22 2017 13:26:25