Growing plants from seed is one of the most economical ways to add plants to your garden. And while starting seeds indoors under lights or in a sunny window is a very popular method, there is an even simpler way. Direct sowing is the method of planting the seeds directly into outdoor garden soil. There is no special equipment, and there are no little pots and flats to mess with. You don't have to worry about transplanting (and the related risk of transplant shock) or hardening off your plants.
That's not to say that direct sowing is foolproof, or that it is the right method for every plant. Plants that require a long growing season—including tomatoes, peppers, and eggplants—won't perform well when direct-sown in cool-weather regions. And plants that require very specific germination conditions are best started indoors. But a surprising number of vegetables, herbs, annuals, and perennials can be sown directly in the garden.
Although direct sowing is an uncertain art, subject to the whims of weather and local wildlife, the enormous cost savings mean that occasional failure is a fair price to pay. A garden started from direct-sown seeds costs a fraction of what it costs to start a garden from potted nursery plants.
When to Direct Sow Seeds in the Garden
When to plant your seeds will depend on the plant species and on the climate in your region. Many vegetable seeds can be planted as soon as the frost is fully out of the ground in the spring and the soil can be readily worked, but some seeds may require warmer soil to ensure that they will germinate and sprout. Some seeds can be sown in the fall, depending on the climate and the seed. Research the plant species and read the requirements listed on the seed packet to learn the best planting time for the seeds you want to grow.
Before Getting Started
Each plant species has its own preferences for soil type, planting time, sun and water requirements, and care. Do some research on the species you are planning to grow in order to learn these preferences. You may find that only certain areas of your garden are suitable, or that your soil type will require some added soil amendments.
Most plants grow best in a soil type known as "loamy"—soil consisting of a balanced mixture of sand, clay, and silt. If your soil is very dense (clay) or very porous (sandy), amending it with organic material such as compost is often recommended. Other amendments may be recommended if your soil's pH level is too acidic or alkaline to grow the plants you want. A soil analysis performed by your university's Extension Service or a commercial testing lab is the best way to learn about your soil and what amendments might be needed.
Equipment / Tools
- Garden fork
- Hose sprayer with mist setting
- Seeds for planting
- Plant markers and string
Prepare the Soil
Start with loose, weed-free, level soil. Take some time to prep the area first by removing all weeds, rocks, and sticks, and break up large clumps of dirt. Loosen the soil with a garden fork, add soil amendments if required, and rake the area into an even, level surface.
A recent soil test can be useful in learning the composition of your garden soil. The test will tell you what amendments are needed to make the soil optimal for the types of plants you want to grow. Almost all soil will be improved by thoroughly blending in some organic material, such as well-decomposed compost, peat moss, or manure, but you don't want soil that is too rich, as not all seeds germinate well in extremely fertile soil.
Prepare the Seeds (if Needed)
The seed pack instructions and your research may indicate that some seeds will do best with some prior preparation. For example, seeds for some plant species need to be slightly softened by soaking them in water before planting. Others may need to be "scarified" by rubbing them against fine sandpaper. Scarifying helps thin the hard shells on some seeds, making them more easily absorb water, germinate, and sprout more easily.
Some of the seeds where scarification is recommended include lupine, nasturtium, sweet pea, and morning glory. Some plants, including perennials like milkweed, need a cold/moist period to germinate, called stratification. While it often occurs naturally when seeds drop from a parent plant in nature, going through the cold, wet winter to weaken the seed coat, you can place these seeds in a container with moist seed starting mix, put them in the refrigerator, and mimic nature. A good book on plant propagation will tell you how to best prepare seeds for direct sowing.
Plant the Seeds
Follow seed packet instructions for planting depth and spacing. Some seeds require light to germinate and prefer to be sown directly on top of the soil. With very tiny seeds, the sowing method is often to pinch the seeds between the thumb and forefinger and sprinkle the seeds into the soil by rubbing the fingers together. Larger seeds usually need to be buried at a prescribed depth—sometimes individually and sometimes in small clusters to ensure proper germination.
The general rule for planting seeds is that they should be planted three times as deep as the diameter of the seed. With very small seeds, this can be a matter of simply sprinkling a light dusting of soil over the seeds. But there's no need to get out the tape measure; seeds aren't all that picky and will often germinate regardless of soil depth.
For edible row crops, you can drive stakes and hang string to ensure that you achieve straight rows when planting. This is not essential, but straight, well-spaced rows can make weeding and other care tasks easier if you have a lot of plants to care for.
Moisten the Soil—and Keep It Moist
The single most important step after planting seeds is to keep the soil evenly moist. Nothing hampers germination more than letting the soil dry out. You do need to be a bit careful about how you water, though. A strong blast from the hose will either wash your seeds completely out of the bed or mess up the spacing if you surface-sowed them. Use a "shower" setting on a hose wand or a "rose" fitting on a watering can to get a gentle flow of water for your seeds.
Mark Planting Location
Make sure to mark where you planted the seeds. Small craft sticks labeled with indelible marker work well for this. This is important whether you planted new annual or perennial seeds in an established ornamental bed or are sowing veggies in your edible garden. Marking seed locations lets you monitor the progress of germination and helps keep track of your garden's layout as planting season progresses. Without labeled markers, it's all too easy to crowd your seeds with additional plantings or to accidentally pull "weeds" that are actually your newly sprouted seedlings.
Recognize the Seedlings, Thin as Needed
Know what your seedlings look like. When they are newly sprouted, it's often hard to tell a weed from, say, a tomato seedling. The first leaves to appear are the cotyledon, or "seed leaves." Wait for a set of true leaves to appear to help you identify your plants well. There are websites you can reference to see what certain seedlings look like, and some seed packets have photos or drawings on them, as well. Knowing what your seedlings look like ensures you won't pull them by mistake while plucking weeds.
Your newly sprouted seedlings may require thinning to maintain optimal spacing for growing to maturity. This is especially true of very tiny seeds, like carrots or celery, which are often planted by sprinkling them over the prepared soil. If allowed to grow too close, they won't be able to mature into sizable plants, so shortly after the seeds sprout, thinning can begin.
Follow the seed packet's recommendations for proper spacing between plants, and make sure to perform the thinning gently, so as to avoid disturbing the fragile new roots of adjoining plants. Rather than pulling the seedings from the ground, some gardeners like to pinch or snip them off at ground level to avoid disturbing the soil.
You may need to thin a second time as the plants grow larger and begin to crowd one another. For many vegetables, the seedlings plucked during thinning make an excellent addition to salads and other dishes.
Care for the Seedlings
Young seedlings are somewhat frail and need careful attention for their first few weeks—especially when it comes to keeping the soil moist. Daily watering using light mist is generally a good idea, but in hot weather, twice-daily watering might be needed.
Follow seed packet recommendations for fertilizing. Normally, feeding is not necessary until the plant gets large enough to begin setting flower buds. With some plants, seed packages may recommend feeding with a diluted fertilizer for the first month or so, until the plants are strong enough to tolerate full-strength feeding.
Also, be diligent in weeding around your young seedlings. Weeds will compete for water, sunlight, and nutrients, so regular weeding is a necessary task.