The Garden View Newsletter

February 2009

Feature Article:
Growing Plants from Seeds

by Richard Anderson

Many people are discovering that growing plants from seed is extremely satisfying, especially as they learn how to do it well. An immense amount of satisfaction can be gained by watching a seed germinate and develop through various stages. In fact, growing plants is considered by many people to be a valuable form of therapy. Whether you are starting vegetables for the home garden or attempting to germinate seeds for the landscape, starting small is not only rewarding, but makes good sense on a limited budget. Growing plants from seeds at first may appear to be quite simple; however, in some cases it is not, and a little research and preparation will be necessary to achieve success.        

All seeds require a set of environmental conditions for germination. The most basic of these environmental stimuli include heat, light, water and oxygen. Replicating the natural environmental conditions for your seed variety is the first step in the germination process. This can be as simple as a germination chamber in the windowsill or stepping up to a small greenhouse or cold frame in the yard.

The idea of heat relates to both the air and soil temperatures. Many seeds, especially those of the vegetable and bedding varieties, prefer a soil around 75°F during the germination and growing process. A cooler air temperature, especially for many of our native species, after germination, is preferential because it more closely mimics natural spring conditions. While in most cases seeds require light for germination, there are species that require darkness in order to germinate. Once germinated, however, all seeds require a light source. The lack of adequate lighting will cause your seedlings to become long and leggy. Fluorescent lighting, placed approximately two inches above the foliage, is generally adequate. Windowsills that provide exposure to indirect sunlight are also suitable. When choosing a potting media, consider one that does not compact readily. Compacted mediums do not allow adequate levels of oxygen to remain in the soil, which is essential for root growth. Watering depends upon the growth stage of the seedling and the temperature of the soil and air. Seeds must be kept moist prior to germination. Warm soil and air temperatures will increase rates of transpiration, requiring more water.  Too much water in the potting media will displace oxygen and may provide a situation where a pathogen can grow and damage or kill your seedlings. Choose seedling containers that provide excellent drainage because this will help prevent any disease.

Don't skimp on seed quality.  Seed packets purchased from a reputable dealer will include viability, also known as the germination percentage, and the year the seed was harvested. Except in special cases, the germination percentage should be 75 percent or higher - preferably 85 percent to 90 percent - and the more recently harvested the better. Look for seed packets that provide tips for germination. These tips will improve your chances for success. Buy only enough seed for your current year's use. Although many seeds can be stored for several years, many others are limited to only one or two year's storage before they rapidly lose their ability to germinate and grow.

Some gardeners save seed from their own garden. This is possible, but you must know where it makes sense and where you may have problems. For example, seed from hybrid sweet corn will not produce the same type of corn as the plants from which you took the seed. Vine crops, such as squash, may cross-pollinate. Seed from cross-pollinated plants will produce plants somewhat different from either variety, sometimes quite inferior.

Select seed for the kinds and varieties of plants adapted to your area. Some that are available may not reach maturity in areas with a short growing season, and it may be necessary to start them indoors. Before starting seeds, make a checklist of the number of days to flower or harvest, and then, using a calendar, count back the numbers of days indicated for each seed variety to determine the proper date to sow the seed. Starting seeds too early, whether due to inexperience or "spring fever," is a common mistake and will lead to plants that are either too large or too old to successfully transition into the garden. Visit the following Extension factsheet for more information, http://extension.usu.edu/files/publications/publication/HG_313.pdf.

Featured Pest:
Damping Off
by Jerry Goodspeed

About this time of the year many people try their hand at starting their own vegetable or bedding plants from seed. As mentioned in the previous article, this can be fun and interesting, but it can also be a little discouraging if all the plants suddenly die. Although there are not many problems with starting seeds at home, one disease called damping off can kill a flat of seedlings overnight. 

Damping off is caused by a fungal disease that likes moist warm conditions. Of course, this is also the environment most seedlings prefer. Damping off affects the seedlings right at the base of the small, new plant. The stem right at the soil level will turn brown and weaken, causing the seedling to fall over and eventually die. Of course, many people see the wilting seedling and apply more water, which simply helps the disease spread.

If you are attempting to grow your own seeds, there are some cultural practices that reduce the likelihood of damping off spoiling all your fun. First, start your seedlings in sterile, new potting soil (consider a seed starter mix). Second, do not plant seeds too thickly. Good air circulation around new seedlings reduces the likelihood of disease spread. New seedlings can also be thinned once they emerge by using a sharp pair of scissors. However, I have found it is really hard for some gardeners to kill anything they have started from seed!   

Make sure you do not over water the new plants. Remember, they have a shallow root system and don't need to be flooded regularly. Once a problem has been detected, remove that tray from the other plants to minimize the risk of spreading the problem. For more information on specific crops, go to http://utahpests.usu.edu/plantdiseases.