Improving Germination Rates

Use Fresh Seed In Proper Conditions

In most cases, we will be planting more seeds than the number of plants we ultimately hope to have in mature form. That is because every seed that we plant does not always germinate. The first questions will always be – is the seed fresh? Gardeners who save seed from last year because they can’t just throw them away often suffer from having poor germination no matter how much trouble they took to save the seed. Buying leftover seed in the fall at bargain rates will often produce a poor germination. In the end, it is best to buy fresh seed when you need it, and do not fool around with old seed if you are looking for success.

Low germination rates may be due to improper soil conditions when the seeds are planted. Remember that each plant has a critical temperature for seed germination. If the ground is too wet, the seeds will rot before they germinate. If the soil is too cold, the seeds will not germinate, no matter how warm the air temperature might be. Wait until the soil temperature and moisture content are optimal for each type of flower or lawn grass. The soil should be lightly cultivated with a rake or tiller and raked fairly smooth. The soil may feel cold, but it should not feel wet or lumpy.

Presoaking Seeds

For some ornamental plants and certain vegetables, germination rates can be improved by soaking seeds before they are planted. This can be done in a dilute solution of seaweed extract or in plain water.

Virtually all seeds presoaked in a dilute seaweed extract solution for no more than 30 minutes have a better germination rate than untreated seeds.

Research suggests that something in the seaweed may increase the respiratory activity of the seeds. To treat seeds and transplants, stir ;1/4 teaspoon of extract into 1 quart of lukewarm water (or one teaspoon of liquid kelp to a gallon of water). Do not use a more concentrated solution, and don't soak seeds for more than 30 minutes, or the benefits will be lost.

Soaking seeds in plain water can also help germination rates for some plants, however you need to be sure it works for the particular plant for which you have seed. Presoaking seeds in most cases takes no more than one hour. For most plants, if you soak them longer, you will hurt germination rather than help it. For some seeds, often noted on the seed packet, longer soaking periods are beneficial. Don’t soak longer than an hour unless you are sure you have good information.

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