By Carl Wilson, Denver County Cooperative Extension Agent, Horticulture
Planting pre-germinated seeds in a fluid gel provides the answer for those anxious to get an early gardening start. This technique is particularly useful in Colorado's high mountain communities, but also will help gardeners along the Front Range. Research from Michigan State University tells us that fluid seeding is used by commercial vegetable growers, as well as by home gardeners in Alaska and other areas with short growing seasons.
Pre-germinating seed indoors is helpful in early spring because sprouted seed will grow in soils too cool for germination. It's easy to sprout seeds on moistened paper towels sealed in a plastic bag for a few days. The difficult part is to sow fragile young seedlings without injury to them. The solution is sowing in a fluid gel.
To make a gel for planting seeds, add one tablespoon cornstarch to one cup of water and bring to a boil. Cool the starch mixture to room temperature before pouring it into a plastic sandwich bag. Gently ease your germinated seeds into the gel and close the bag with a twist tie. If the weather is not right for planting, store the gel bags in the refrigerator for a few days until conditions improve. To plant, snip the corner off the plastic bag and squeeze the gel and seedlings into the planting furrow as you would toothpaste from a tube.
Attempts to fluid sow pre-germinated seeds in March should be confined to cool season vegetables such as carrots and other root crops, and leafy vegetables such as lettuce and cabbage.
While fluid seeding is useful to make an early start, it is best used in combination with other gardening techniques. Pre-warm the soil before sowing by covering with clear plastic for several weeks. Floating row cover fabric, spread over the seeded rows, provides additional protection from changeable spring temperatures.
In Colorado's mountain communities, these techniques will help extend the short growing season. In Front Range areas, these methods can help cool season vegetables complete growth before hot temperatures arrive in June. High temperatures often knock out cool season vegetables before they can complete growth and be productive. Fact sheets listing both root crops and leafy vegetable crops suitable for planting in Colorado are available from your local Colorado State Cooperative Extension office.
Photograph courtesy of Judy Sedbrook.
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010