In the germination process there are three steps which occur to allow the plant to grow from seed. The first step of awakening or activation requires the seed to absorb moisture. This step is mostly a physical process in which the seed does no work. Once the seed accumulates a certain amount of water in its cells, the second step is initiated. Digestion and translocation allow for more water uptake and cell processes to begin. The protein-making structures that are activated allow for plant growth and the reserve materials (carbohydrates) in the seed to be broken down to provide for materials once the seedling begins to grow. The final step is the actual growth of the plant by cell division and cellular elongation. New cells are formed and all the cells begin to expand. The cotyledons, or first leaves appear, and the radicle, or growth point of root, elongates.
There are many factors which influence germination, but to simplify matters, the environmental factors most easily controlled by the home gardener or hobbyist will be covered here. Water availability can determine the success or failure of germination. The higher the temperature, the greater amount of water a seed can take up. Seeds need a moderate amount of water-enough to keep the soil lightly moist, but not so much that the soil stays water-logged. This will allow the seed to take up the needed amount of water to start germinating without causing rot.
Starting Herbaceous Plants Indoors:
1. Use a clean container. Any container that will hold medium and provide drainage will work.
2. Medium should be sterile, porous enough to hold air and water, and packed firmly into container. (1 part compost, 1 part sand or vermiculite, 1 part peat moss or coconut coir is a standard mix or if a soilless mix is preferred use 4 quarts fine vermiculite, 4 quarts milled sphagnum peat moss, 1 tablespoon superphosphate, and 2 tablespoons ground limestone.)
3. Seeds should be planted to a depth of 2-3 times of the narrowest part of their diameter, if seeds are fine they can be sprinkled over the surface. All seeds should be tamped firmly after planting.
4. Temperature for most seeds should be maintained at 70-750 F during the day and 60-650 F at night. This can be achieved by using heat mats. If using artificial lighting for light and temperature control, make sure not to keep the lights on all the time. Some seeds have a required length of time without light to stimulate germination called a dark period. A timer that allows for a solid period of 6-8 hours of dark should meet most seeds’ requirements.
5. Once germination occurs, lower daytime temperature to 650 F and increase light to help produce thick stems and stocky plants.
6. Before transplanting, seedlings must be hardened off to decrease the amount of shock and increase productivity. This is done by gradually lengthening exposure of the plant to its new environment over a period of a week.
7. To transplant, thoroughly water roots of plant before and after planting and give a mild fertilizer right after planting.
Information about Extension Solutions for Homes and Gardens can be found on the UGA extension website, www.caes.uga.edu/extension/cherokee ; or contact the Cherokee County Extension Office, 1130 Bluffs Parkway, Suite G49, Canton, GA, 30114, 770-721-7803. The Georgia Master Gardener Extension Volunteer Program is a volunteer training program offered through county offices of the UGA extension. Follow Cherokee County Master Gardeners on facebook at www.facebook.com/cherokeemastergardeners for gardening tips as well as upcoming seminars.