Pregermination. Another method of starting seeds is pregermination. This involves sprouting the seeds before they are planted in pots or in the garden. It reduces the time to germinate as the temperature and moisture are easy to control, and it guarantees a high percentage of germination since none will be lost to environmental factors. Using a pan, lay seeds between the folds of a cotton cloth on a layer of vermiculite or similar material. Keep it moist and in a warm place. When roots begin to show, place the seeds in containers or plant them directly in the garden. When transplanting seedlings, be careful not to break off tender roots. Continued attention to watering is critical.

When planting seeds in a container that will later be set out in the garden, place one pregerminated seed in a 2 to 3 inch container. Plant the seeds to only half the recommended depth. Gently press a little soil over the sprouted seed and then add about ¼ inch of milled sphagnum or sand to the soil surface. These materials will keep the surface uniformly moist and are easy for the shoot to push through. Keep the pots in a warm place and care for them just as for any other newly-transplanted seedlings.

A convenient way to plant small, delicate, pregerminated seeds is to suspend them in a gel. Make a gel by blending cornstarch and boiling water to a consistency that is thick enough for the seeds to stay suspended. Be sure to cool the gel thoroughly before use. Place the gel and seedlings in a plastic bag with a hole in it. Squeeze the gel through the hole along a premarked garden row. Spacing of seeds is determined by the number of seeds in the gel. If spacing is too dense, add more gel; if its too wide, add more seeds. The gel will keep the germinating seeds moist until they become established in the garden soil.

Watering. After the seed has been sown, thoroughly moisten the planting mix. Use a fine mist spray or place the containers in a pan or tray with an inch of warm water in the bottom. Avoid splashing or excessive flooding, which might displace small seeds. When the planting mix is saturated, set the container aside to drain. The soil should be moist but not wet.

Ideally, seed flats should remain sufficiently moist during the germination period without having to add water. One way to maintain moisture is to slip the entire flat or pot into a clear plastic bag after the initial watering. The plastic should be at least 1 to 1½ inches from the soil. Keep the container out of direct sunlight or the high temperatures may harm the seeds. Many home gardeners cover their flats with panes of glass instead of a plastic sleeve. Be sure to remove the plastic bag or glass cover as soon as the first seedlings appear. Surface watering can then be practiced if care and good judgment are used.

Problems related to hand watering are lack of uniformity, over watering and drying out. Excellent germination and moisture uniformity can be obtained with a low-pressure misting system. On springtime days, 4 seconds of mist every 6 minutes or 10 seconds every 15 minutes seems to be satisfactory. Bottom heat is an asset with a mist system. Subirrigation or watering from below may work well to keep the flats moist. However, since the flats or pots must sit in a constant water level, the soil may absorb too much water and the seeds may rot due to lack of oxygen.

Temperature and light. Several factors assuring good germination have already been mentioned. The last item, but by no means the least important, is temperature. Since most seeds germinate best at an optimum temperature that is usually higher than most nighttime temperatures, special warm areas are often necessary. The use of thermostatically-controlled heating cables is an excellent way to provide constant heat.

After germination and seedling establishment, move the flats to a light, airy and cool location. Temperatures should range from 55° to 60°F at night and 65° to 70°F during the day. This prevents soft, leggy growth and minimizes disease problems. Some crops, of course, may germinate or grow best at different temperatures and must be handled separately from the bulk of the plants.

Seedlings must receive bright light after germination. If possible, place them in a window facing south. If a large, bright window is not available, place the seedlings under a fluorescent light. Use two 40-watt, cool white fluorescent tubes or special plant growth lamps. Position the plants 6 inches from the tubes and keep the lights on them for about 16 hours each day. Raise the lights as the seedlings grow.

Transplanting and handling seedlings. If plants have not been seeded in individual containers, they must be transplanted to give them proper growing space. One of the most common mistakes made by plant growers is to leave the seedlings in the seed flat too long. The ideal time to transplant young seedlings is when they are small, and there is little danger from setback. This is usually about the time the first true leaves appear above or between the cotyledon leaves (the cotyledons or seed leaves are the first leaves the seedling produces). Do not let plants get hard and stunted or too tall and leggy.

Seedling growing mixes and containers may be purchased or prepared by methods similar to those mentioned for germinating seed. However, the medium should contain more plant nutrients than a germination mix. Some commercial soilless mixes have fertilizer already added. When fertilizing, use a soluble house plant fertilizer at the dilution recommended by the manufacturer about every 2 weeks after the seedlings are established. Remember that young seedlings are easily damaged by too much fertilizer, especially if they are under any moisture stress.

To transplant, carefully dig the small plants up with a knife or wooden plant label. Let the group of seedlings fall apart and pick out individual plants. Gently ease them apart in small groups; this makes it easier to separate individual plants. Avoid tearing roots in the process. Handle small seedlings by the leaves, not the delicate stems. Punch a hole in the medium into which the seedling will be planted. Make the hole the same depth that the seedling was growing in the seed flat. Small plants or slow growers should be placed about 1 inch apart, while rapid-growing, large seedlings should be placed about 2 inches apart. After planting, firm the soil and water gently. Keep newly transplanted seedlings away from direct heat in the shade for a few days, or place them under fluorescent lights. Continue watering and fertilizing as was done in the seed flats.

It is easy to transplant most plants and they can be started indoors, but a few plants are difficult to transplant. These are usually directly seeded outdoors or are sown directly into individual containers indoors. Examples include zinnias and cucurbits, such as melons and squash.

Containers for transplanting. A wide variety of containers are available to choose from for transplanting seedlings. Containers should be economical, durable and space efficient. The type of container selected will depend on the type of plant to be transplanted and individual growing conditions. Standard pots may be used, but they waste a great deal of space and may not dry out rapidly enough for the seedling to have sufficient oxygen for proper development.

There are many types of containers available commercially. Pressed peat containers can be purchased in various sizes. Individual pots or strips of connected pots fit closely together, are inexpensive and can be planted directly in the garden. When setting out plants grown in peat pots, be sure to completely cover the pot. If the top edge of the peat pot extends above the soil level, it may act as a wick and draw water away from the soil in the pot. To avoid this, tear off the top lip of the pot and plant it flush with the soil level.

Community packs have enough room to plant several plants. These inexpensive containers are generally made of pressed paper or fiber. The main disadvantage of a community pack is that the roots of the individual plants must be broken or cut apart when separating them to put out in the garden.

When soaked in water, compressed peat pellets expand to form compact individual pots. They do not waste space, do not fall apart as readily as peat pots and can be directly set in the garden. If you wish to avoid transplanting altogether, compressed peat pellets are excellent for direct sowing of seedlings.

Community packs and cell packs, which are strips of connected individual pots, are also available in plastic. These are frequently used by commercial bedding plant growers as they withstand frequent handling.

In addition, many home-owners use a variety of household materials for containers. Homemade containers should be deep enough to provide adequate soil and should have plenty of drainage holes in the bottom.

Hardening plants. Hardening is the process of altering the quality of plant growth to withstand changes in environmental conditions that occur when plants are transferred from a greenhouse or home to the garden. A severe check in plant growth may occur if plants produced in the home are planted outdoors without undergoing a transition period. Hardening is less critical for crops planted later in the season than for early crops when adverse climatic conditions can be expected.

Hardening is accomplished by gradually lowering temperatures and relative humidity while also reducing water. This results in an accumulation of carbohydrates and a thickening of cell walls. The change from a soft, succulent type of growth to a firmer, harder type of growth is desired.

Hardening should be started at least two weeks before planting in the garden. If possible, plants should be moved to a 45° to 50°F temperature indoors or outdoors in a shady location. A coldframe is excellent for this purpose. When put outdoors, plants should be shaded and then gradually moved into sunlight by increasing the length of exposure each day. Do not put tender seedlings outdoors on windy days or when temperatures are below 45°F. Even cold-hardy plants will be hurt if exposed to freezing temperatures before they are hardened. After proper hardening, however, they can be planted outdoors and light frosts will not damage them.

The hardening process is intended to slow plant growth. If carried to the extreme of actually stopping plant growth, significant damage can be done to certain crops. For example, cauliflower will make thumb size heads and fail to develop if hardened too severely. Cucumbers and melons will also stop growth if hardened incorrectly.

Though ferns are more easily propagated by other methods, some gardeners like the challenge of raising ferns from spores. One tested method for small quantities is described below.

Ingredients needed:

• Mature fern spores
• Distilled water
• 3-4 drops dishwashing detergent
• Eye dropper
• Jiffy peat pellets
• Clear shallow dish
• Clear disposable plastic cup

Begin by soaking jiffy pellets in water. After about an hour, they will at least double in size and will be ready to use. While the jiffy pellets are soaking, put 3-4 drops of dishwashing detergent in 1 cup of distilled water in a separate container. Place your fern frond over the soapy water solution. Now place the jiffy pellet on a clear shallow dish and gently pull away the netting from the top of the jiffy pellet. Using an eye dropper, extract liquid from the soapy water solution and gently squeeze it over the top of the jiffy pellet. The solution will contain many fern spores that will come into contact with the jiffy pellet. Cover the jiffy pellet with a clear disposable plastic cup.

It may take up to a month or more for the spores to germinate. Keep moist at all times. The sexual stage, called the prothallus, will initially develop from each spore, forming a light green mat. Mist lightly once a week to maintain high surface moisture; the sperm must be able to swim to the archegonia (female parts). Fertilization should occur after 3 weeks.

A green mat should form on the top of the jiffy pellet and soon the formation of fern fronds will be evident. Gradually reduce the humidity so that they can survive in the open by either putting small holes in the plastic cup or lifting the cup slightly each day. After several weeks pull apart the jiffy pot and transplant ferns to individual containers

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