As a substitute for in-person programming, we’re offering a series of posts on starting a vegetable garden. This science-based information comes from the Seed to Supper program, developed by the Oregon Food Bank. During these difficult times, the Oregon Food Bank welcomes your donations.
OSU is also offering its vegetable gardening class online.
Learning to read seed packets will help you make good decisions when you grow crops from seed. All seed packets list the same basic information: when to plant, how deep to plant, distance between plants, and days to harvest.
Some crops germinate in relatively cool weather, while others (like corn, eggplant and tomatoes) need warmer temperatures. A soil thermometer will help you make decisions about when to plant seeds outdoors. On the Oregon coast, early planting crops include cabbage, carrots, onions, peas, potatoes, and radishes; by mid-April, our soils are generally warm enough for these seeds to germinate. Keep in mind, however, that clay soils warm more slowly than other soil types.
Loosen the soil using a digging fork or shovel, then rake the seedbed smooth to create a loose, even “tabletop” to your bed. To make less work for yourself, spread your compost and fertilizer before you loosen the soil. Mix them in as you work the bed.
When you sow your seeds, you can choose one of these patterns: row planting, banded planting, and hill planting. Most seed packets have directions for planting in rows. The packet will tell you how deep the rows should be, how far apart to plant the seeds, and how far apart to space the rows. Draw rows in the soil with your finger or a garden tool. Sow large seeds one by one, or sprinkle in smaller seeds. As insurance, sow twice as many seeds as you need—you can thin them later.
Check the seed packet to see how deep the seeds should be, then cover them with that amount of soil. Covering the seeds should be your last step so that you can see if you missed any spots. To keep your rows straight, you may want to use string lines as a guide. Pound in a stake at each end of the row and tie a string between the stakes—then follow the string as you plant.
Row planting works for all crops, and it allows for hoeing weeds, but the distance between rows can waste space in a small garden. For banded planting, create a single wide row and broadcast seeds evenly within it. For hill planting, which is a good way to plant large seeds, plant several seeds in a small cluster.
To avoid the problem of too many seeds coming out at once as well as the problem of seeds sticking to your fingers, here's a simple tip: Crease the seed packet at the front and back so it resembles an open diamond. Holding the packet above the area you want to sow, tap the bottom crease lightly with a pencil so that the seeds dispense evenly at the top crease.
How deep to plant seeds depends on the crop—check your seed packet for information. If there are no directions on your seed packet, follow this rule: Sow as deep as 3 to 4 times the longest part of the seed. For instance, if the seed is ¼ inch long, sow it 1 inch deep. If you soil is heavy, you can sow your seeds less deeply and cover them with light potting soil. If seeds are too deep, they may never germinate. If not deep enough, they may wash away or be carried off by birds.
Labeling at planting time can help you remember what you’ve planted. Include the date, too, either on the label or in your garden journal. Cut up old yogurt containers or use popsicle sticks as plant tags—write on them with a permanent marker.
Seeds need moisture to germinate. Mist or lightly water often so that the soil is moist (like a wrung-out sponge), but not soggy.
Use a hose nozzle with a mist setting to avoid washing the seeds away. Hold the nozzle above the soil until the water starts to puddle. Let the water soak in, then continue watering until it puddles again. Do this several times for an even watering. Water new seedbeds every day or two until the seedlings are established (more often in hot weather). Let the soil dry slightly between watering.
Begin thinning when the seedlings’ first “true leaves” develop. True leaves are a plant’s mature foliage—they look different from first leaves. Remove weak, small seedlings, and leave the stronger ones to grow. When you thin, you can snip the seedlings at surface of the soil or gently pull them up by the roots. Water well after thinning to keep the remaining plants from drying out. Thin weekly until each plant has a “footprint” worth of growing space.
Next up: Transplants