Starting seeds indoors
Starting seeds indoors is one of the greatest joys of the vegetable growing season. In the dead of winter, we witness the magical transformation of a seed into new life. Gardening with kids provides a unique opportunity to teach life cycle lessons, and if you play your cards right, nutritious eating habits. I’ve had success on both counts in my own backyard vegetable garden: www.http://northernvirginiagardener.blogspot.com/
Knowing when to start seeds indoors takes some backward thinking. Find out the average date of the last frost in your area and the number of weeks before that date you should start a particular seed (the number of weeks varies and is listed on the seed package). Then count backwards on the calendar from the average last frost date. Most seeds should be started six to eight weeks before the last frost date. Some seeds can be started a few weeks before it, while others may need a lead-time of 12 to 14 weeks. If you start seeds too early, you will have to keep the seedlings inside too long, and they will be weak by transplant time. For vegetable planting dates outdoors, visit ttp://www.hgic.umd.edu/_media/documents/publications/planting_dates.pdf.
To start seeds indoors, it is important to have enough light. More homegrown seedlings are probably lost to this one factor than to any other. Vegetable seedlings grown under low-light conditions are likely to be leggy and weak, and many will fall over under their own weight after they are 3 to 4 inches tall. If you do not have a sunny room or back porch with a southern exposure, you will probably need supplemental lights. A simple, fluorescent, shop light with one warm-white and one cool-white bulb (or with grow lights) will suffice.
It is probably easiest to use a soilless or peat-lite mix to start seedlings, since garden soil contains disease organisms that can be highly destructive to small plants. Soil can be sterilized in the oven by baking it at 200ƒ F until the internal soil temperature is 180ƒ F. It should be held at that temperature for 30 minutes. This is a smelly process, but it works. Garden soil for use in containers should be conditioned with compost and perlite to prevent excess moisture retention and/or shrinkage . You can mix your own peat-like mix if you prefer; 50% vermiculite and 50% fine sphagnum peat is excellent for starting seeds. Fertilizer at half the normal strength may be added to the mixture. Mix well before using.
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 reusable after cleaning. 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. Many seed starting kits are now available and provide everything you will need, but remember that these are used as part of a hobby and not as a way to save money instead of buying plants at a nursery.
Regardless of the type of container chosen, fill it three quarters full with seed-starting mixture and sow the seeds. Cover to the specified depth, and water the mix. 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 or diminished 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 preformed 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 or cube 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 two to three 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. The following chart gives optimum soil temperatures.
Plant Production Data Chart
Crop Days to Emergence
From Seeding Optimum Germination
Soil Temp. Range (°F) Number of Weeks
to Grow Transplants
Beans 5-10 65° – 85° *
Beets 7-10 50° – 85° *
Broccoli 3-10 50° – 85° 5 – 7
Cabbage 4-10 50° – 85° 5 – 7
Carrots 12-18 50° – 85° *
Cauliflower 4-10 50° – 85° 5 – 7
Celery 9-21 50° – 65° 10 – 12
Chard, Swiss 7-10 65° – 85° *
Corn, sweet 5-8 65° – 85° *
Cucumber 6-10 65° – 85° 4 (peat pots)
Eggplant 6-10 65° – 85° 6 – 9
Lettuce 6-8 50° – 65° 3 – 5
Melons 6-8 65° – 85° 3 – 4 (peat pots)
Okra 7-10 65° – 85° *
Onion 7-10 65° – 85° 8
Parsley 15-21 50° – 85° 8
Peas 6-10 50° – 65° *
Pepper 9-14 65° – 85° 6 – 8
Potatoes, Sweet (slips) 65° – 85° 5 – 6
Radish 3-6 50° – 65° *
Spinach 7-12 50° – 65° *
Squash 4-6 65° – 85° 3 – 4 (peat pots)
Tomato 6-12 65° – 85° 5 – 7
Turnip 4-8 50° – 65° *
* transplants not recommended
When planting the fall garden in midsummer, the soil will be warm and dry; therefore, cover the seeds six to eight 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 shallow mulch or by covering the row with a board until the seeds have sprouted. Shading the area may be helpful to keep the soil cooler for seed germination, especially when planting cool-weather crops in summer. Seed that requires a lower germination temperature may benefit from being kept in the refrigerator for two 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.
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 so that it is in direct contact with seeds improves uptake of soil moisture by the seed, hastening germination. Water in the seeds. When plants have grown to 4 to 6 inches tall, thin according to seed packet instructions to provide adequate room for growth.
Wide row or banded planting
Many crops may be sown in wide rows or bands instead of in long, single rows. Crops of spinach, bean, pea, beet, lettuce, and carrot are especially suited to this type of culture. Sow seed evenly over the area, then rake it in, firming soil over the seeds. Thin young plants to allow room for growth.
Larger vegetables, such as melons, squash, sweet corn, and cucumbers, may be planted in hills or groups of seed. Soil is mounded to a foot or so in diameter, at the recommended spacing. Plant four to six seeds per hill, firming the soil well. Thin the seedlings to three to five plants per hill.
Transplants for the Garden
Most gardeners use transplants in the garden at some time or another to give long-season plants a chance to grow to maturity under their preferred weather conditions or just to lengthen the harvest season. Cool-season crops, such as head lettuce, broccoli, and celery, would not have a chance to reach their prime harvest stage in most places in Virginia in spring if not given those extra weeks indoors to get a head start. Tomatoes would certainly have a short harvest period in all but southeastern Virginia if started from seed in the ground, and peppers and eggplants might not produce at all if not grown from transplants.
Due to the amount of time, attention, and need for controlled growing conditions, many gardeners prefer to purchase plants for their gardens. However, for a larger choice in varieties and the control of plant production from seed to harvest, others choose to start their own transplants.
Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Rick D. Rudd, Interim Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; Wondi Mersie, Interim Administrator, 1890 Extension Program, Virginia State, Petersburg. adapted from articles by Diane Relf, Extension Specialist, Environmental Horticulture, Virginia Tech, and Alan McDaniel, Extension Specialist, Environmental Horticulture, Virginia Tech and Audrey Cooke, Frederick County Master Gardener