Commonly grown annual flowers and vegetables are usually very easy to start from seed. Just pop them into a sterile media such as perlite or vermiculite and keep them moist and warm. Before long, little seedlings will be sticking their heads up looking for the light.

Many seeds from perennial plants are just as easy to start. Pop them into the medium and they come up in a few days or weeks. However, the seeds of some flowering perennials and most species of trees and require special care. These plants originated in regions that presented unique climate problems that had to be overcome. Depending on the "coping mechanism" adapted by the plant, these seeds require special treatments before they will germinate.

The most common seed treatments are stratification and scarification. Many species originated in deciduous forests where seeds drop to the ground and are covered by leaves in the fall. They spend the winter encased in this moist, cool environment before germinating in the warm, moist conditions of spring. The embryo inside such seed is immature and unable to grow until it has been nurtured in this manner. This delayed germination is vital to the survival of the species. The seeds are set in the autumn. If they germinated immediately after falling to the ground, the tender seedlings would be killed by the winter cold.

Stratification is the process of simulating nature by exposing seeds to cool, moist conditions for a number of weeks or months. Take peat moss and soak it in water until it is saturated. Then, squeeze out as much water as possible with your hands. Place a layer of the moist moss in the bottom of a plastic container. Place the seeds on this layer and fill the rest of the container with peat moss. Store it in the refrigerator for 3 to 6 months depending on the species of plant. Remove the seeds and plant them in the normal manner.

Another mechanism used by plants to prevent their seeds from germinating too soon is the formation of an extremely hard seedcoat. In nature, these seeds may lay dormant until weathering action and micro-organisms break through the hard seed coat. Seeds from a single crop may germinate over several succeeding years. This increases the likelihood that at least some of them will emerge under favorable growing conditions and survive to perpetuate the species.

To get these seeds to germinate immediately, the seed coat must first be softened or broken so that water can penetrate and the seedling can emerge. This process is called scarification.

Seeds may be scarified a number of ways. Nicking the seedcoat with a file or sandpaper is probably the easiest method. Soaking seeds in a mild acid solution is often used by commercial growers. Some seeds may be scarified simply by soaking them in warm water over-night.

To determine the requirements of a particular species, check the seed packet. If you are collecting seed directly from the plant or got them from a friend, there are several references which should be helpful. Park's "Success With Seeds" is an excellent reference for perennial and annual seed germination. For trees and shrubs, the USDA's "Seeds of Woody Plants in the United States" contains the requirements of just about every tree that grows around here. You can find these at the library or give me a call since I have both of them on my shelf.


Note: We have provided some general information and observations on this topic aimed at the home gardener. Before you take any serious action in your landscape, check with your state's land grant university's Cooperative Extension Service for the most current, appropriate, localized recommendations.


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