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Vegetable Garden


  MG Manual Reference
Ch.10, pp. 8 - 12
[Seed for the Garden: seed | soil temperature ]

Choosing and purchasing vegetable seeds is one of the most enjoyable gardening pastimes. Thumbing through colorful catalogs and dreaming of the season's harvest is one way to make winter seem a little warmer. Seed purchased from a dependable seed company will provide a good start toward realizing that vision of bounty. Keep notes about the seeds you purchase - their germination qualities, vigor of plants, tendencies toward insects and disease, etc. From this information you can determine whether one seed company is not meeting your needs, or whether the varieties you have chosen are unsuitable for your area or gardening style. For example, if powdery mildew is a big problem on squash family plants in your area, the next year you may want to look for mildew-resistant varieties.
Saving seed
Saving your own vegetable seed is another pleasurable activity. It offers a sense of self-sufficiency and saves money. You can maintain a variety that is not available commercially, which helps to perpetuate a broad genetic base of plant materials. Breeders often search for old-time varieties when attempting to improve commercial plants, since the heirloom vegetables (as they are sometimes called) often have inbred disease- and pest-resistance or cold-hardiness. Participation in a seed-saver's exchange can be a rewarding experience. Extra seeds that you have may be traded for unusual types that are not available through other sources.
There are certain considerations that should be kept in mind when saving seed, however. Hybrid varieties are not likely to be the same as the parent plants; therefore, only open-pollinated varieties should be used for home seed production. Some seed dealers have responded to the increasing interest in seed-saving by clearly marking open-pollinated varieties in their catalogs. Another consideration in saving seed is the possibility of carrying seed-borne diseases into the next year's crop. Many commercially grown seeds are grown in dry areas unsuitable to fungal, viral, and bacterial diseases which may be present in your region. Take care to control diseases which can be carried in seed. Another weather-related factor is the speed of drying of seeds, which can be adversely affected by frequent rains and/or humidity. And finally, if you've ever saved squash seed during a season in which you had more than one type of squash planted, you have probably seen the weird results that may be obtained from cross-pollination! Saving seeds from cross-pollinated crops is not generally recommended for the novice because of problems with selection, requirements for hand pollination and isolation, biennial habits, and genetic variability.
Some common self-pollinated annual plants from which seed may be saved include lettuce, beans and peas, herbs, and tomatoes.
Beans and Peas
Saving beans and peas: Allow seed pods to turn brown on the plant. Harvest pods, dry for 1 to 2 weeks, shell, and then store in a cool (below 50° F.), dry environment in a paper bag.
On an extended trip, make special arrangements so that plants will not be frozen or damaged by cold weather. Many foliage plants will be damaged considerably if the temperature drops much below 50° F, so maintain as warm a temperature as possible around these plants when transporting them from one location to another.
Saving lettuce seed: Cut off seed stalks when fluffy in appearance, just before all the seeds are completely dried. Seeds will fall off the stalk and be lost if allowed to mature on the plant. Dry the harvested seed stalk further, shake seeds off, and then store in a cool, dry environment in an envelope or small glass jar.
Saving herb seeds: Herbs vary in the way their seeds are produced. In general, allow herb seeds to stay on the plants until they are almost completely dry. Some seed heads, such as dill, will shatter and drop their seeds as soon as they are dry. Watch the early-ripening seeds; if they tend to fall off, harvest the other seed heads before they get to that point, leaving several inches of stem attached. Hang several stems upside down, covered with a paper bag to catch falling seed, in a warm, dry place until the drying is complete. Remove seeds from the seed heads and store in envelopes or small glass jars. Some herb seeds, dill, celery, anise, cumin, coriander, and others are used for flavoring and are ready to use once dry.
Saving tomato seeds: Pick fruit from desirable plants when ripe. Cut fruit and squeeze out pulp into a container. Add a little water, then let ferment 2 to 4 days at room temperature, stirring occasionally. When seeds settle out, pour off pulp and spread seeds thinly to dry thoroughly. Store in an envelope or glass jar in a cool, dry place.
For all kinds of saved seeds, be sure to mark the storage containers clearly with permanent (preferably waterproof) ink, indicating the variety and date saved. Seeds will remain viable for some time if properly stored. To test for germination, sprout seeds between moist paper towels; if germination is low, either discard the seed or plant enough extra to give the desired number of plants.
(For additional information on seed storage refer to Chapter 7, Plant Propagation.)
Table 10.2

VIABILITY OF VEGETABLE SEEDS (Average number of years seeds may be saved)

Vegetable Years Vegetable Years
Asparagus 3 Leek 1
Bean 3 Lettuce 5
Beet 4 Muskmelon 5
Broccoli 4 Mustard 4
Brussels sprouts 4 Okra 2
Cabbage 4 Onion 1
Carrot 3 Parsley 2
Cauliflower 4 Parsnip 1
Celery 5 Pea 3
Chinese cabbage 4 Pepper 3
Collard 4 Pumpkin 4
Corn, sweet 1 Radish 4
Cress, water 5 Rutabaga 4
Cucumber 5 Spinach 4
Eggplant 5 Squash 4
Endive 5 Tomato 3
Kale 4 Turnip 5
Kohlrabi 4 Watermelon 5
Many types of containers can be used to start seeds. Flats or other large containers may be used; plant in rows and grow seedlings until they have one or two sets of true leaves, then transplant into other containers for growing to the size to transplant outdoors. Seedlings may also be started in pots, old cans, cut-off milk cartons, margarine tubs, egg cartons, or other throwaways. The pop-out trays found at garden centers are easy to use and re-usable. Peat pots are nice, especially for large seeds. Sow one or two large seeds directly in each peat pot.
Thin to one seedling per pot. Peat pots may be planted directly in the garden; do not allow the edges of the pot to stick out above the soil, since they will act as a wick and moisture will evaporate from this exposed surface.
Regardless of the type of container chosen, fill it 3/4 full with seed-starting mixture and sow the seeds. Cover to the specified depth and water the mix. If your home is dry, it may help to cover the containers with plastic wrap to maintain a steadier moisture level. Seeds and seedlings are extremely sensitive to drying out. They should not be kept soaking wet, however, since this condition is conducive to damping-off, a fungus disease deadly to seedlings. Damping-off can be prevented by sprinkling milled sphagnum moss, which contains a natural fungicide, on top of the soil.
Another option is to use peat pellets or cubes, which are pre-formed and require no additional soil mix. The pellets or cubes are soaked until thoroughly wet, then seeds are planted in the holes provided. The whole pellet may then be planted without disturbing the roots. The only disadvantage to this method is the expense.
Starting seed outdoors
Many seeds may be sown directly in the garden. If garden soil is quite sandy, or is mellow with a high content of organic matter, seeds may be planted deeper. Young seedlings can emerge quite easily from a sandy or organic soil. If garden soil is heavy with a high silt and/or clay content, however, the seeds should be covered only 2 to 3 times their diameter. In such soils, it may be helpful to apply a band of sand, fine compost, or vermiculite 4 inches wide and 1/4 inch thick along the row after seeds are planted. This will help retain soil moisture and reduce crusting, making it easier for seedlings to push through the soil surface.
Soil temperature has an effect on the speed of seed germination. In the spring, soil is often cold and seeds of some plants will rot before they have a chance to sprout. Table 10.4 gives the optimum soil temperatures.
When planting the fall garden in midsummer, the soil will be warm and dry. Therefore, cover the seeds 6 to 8 times their diameter. They may need to be watered each day with a sprinkler or a sprinkling can to promote germination. Moisture can also be retained with a shallow mulch or by covering the row with a board until the seeds are up. Shading the area may be helpful to keep the soil cooler for seed germination, especially when planting cool-weather crops in summer. Seed which requires a lower germination temperature may benefit from being kept in the refrigerator for 2 weeks before planting, or from pre-sprouting indoors. Pre-sprouting is a useful technique for planting in cold soils, as well. However, seed must be handled very carefully once sprouted to prevent damaging new root tissue.
Row Planting
A string stretched between stakes will provide a guide for nice straight rows, if desired. Use a hoe handle, a special furrow hoe, or a grub hoe to make a furrow of the appropriate depth for the seed being planted. Sow seed thinly; it may help to mix very small seed with coarse sand to distribute the seeds more evenly. Draw soil over the seed, removing stones and large clods. Firming soil over seeds improves uptake of soil moisture, hastening germination. Water the seeds in to improve soil/seed contact. When plants have grown to 4 to 6 inches tall, thin according to seed packet instructions to provide adequate room for growth.
Broadcast planting
Many crops may be sown in wide rows or beds instead of in long, single rows. Crops such as spinach, beans, peas, beets, lettuce, and carrots are especially suited to this type of culture. Sow seed evenly over the area, then rake it in. Firm soil over the seeds. Thin young plants to allow room for growth.
Hill Planting
Larger vegetables such as melons, squash, corn, and cucumbers may be planted in hills. Soil is mounded to a foot or so in diameter, at the recommended spacing. Plant 4 to 6 seeds per hill, firming the soil well. Thin the seedlings to 3 to 5 plants per hill.

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