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The first step to improving germination is understanding what seeds are and how they do what they do. A seed is a completely self contained little miracle that carries inside it everything it needs to sprout and grow into a seedling. It has a food store and all the important information it needs to grow, including knowing when the conditions are right for it to sprout. Once the seed is formed, it is dormant. It’s just sleeping, and breathing. Yes, it is breathing: it is taking in oxygen and giving off carbon dioxide. Seeds in this state can last a long time and still remain viable, because it takes very little energy to remain in the dormant state. To keep seeds dormant, and extend their viability, keep them in a cool dry place out of direct sunlight.
1. Be consistent for consistent results
Once a seed perceives that the conditions are right for sprouting, it will begin to transform. At this point it becomes active and the germination process is set into motion. Germination requires a consistent optimal environment to produce a successful sprout.
Any interruption in this process will reduce success., The seed has just so much stored energy and if you give it the signal to start its journey and then turn that signal off, it will not have enough energy to re-start the process. Drying out or exposure to extreme temperature swings can both cause the germination cycle to fail.
Be certain once you begin to germinate seeds that you maintain their moisture and temperature, cool nights that are a natural part of the process for seed out of doors is one thing, searing heat, or drought will stop germination.
2. Use appropriate seed starting mix for best results
Seeds do not need fertilizers or plant food to sprout and these nutrient sources can inadvertently feed bacteria, moss, algae or other organisms which will wait for the seed to sprout and then eat your seed.
Prepare your germinating mix using equal parts peat moss and perlite or a commercial seed starter blend. Potting soil can be used if it is not pre-fertilized. Well composted material can also be used; be careful to avoid any partially composted materials. Compost should be fine and crumble easily with no large pieces.
3. Use Clean Containers with Good Drainage Holes for Sprouting Seeds
Reduce the risk of ‘damping off’ of young seedlings by making sure containers are clean. Clean containers reduce bacteria, molds, fungus and other potentially hostile organisms from developing and harming the germinating seed.
Be certain your container has adequate drainage by making holes in the bottom of the container. Alternatively, you can use rolled newsprint or newspaper or peat pots which allow moisture to evaporate through their walls. This also allows the potting mix to draw water in through the sides and bottom of the container.
4. Clean Used Containers with Hydrogen Peroxide, not Bleach
Clean any used containers to be used for sprouting seeds with a 3% hydrogen peroxide solution. The best method is to first wash the container with dish soap and warm water and then rinse in a bath of 3% h2o2 for ten to fifteen minutes. This has the added benefit of being completely non-toxic to the future plant or to you, because the ‘residual by-product’ of h2o2 is oxygen; something the seed actually needs to sprout properly.
5. Properly Prepare Your Container with Planting Mix
Fill containers loosely and shake gently to get the mix to settle. Tapping the container lightly on a table or counter also works to uniformly fill the container without compacting it too much.
Use the edge of a clean knife or trowel to scrape across the top of the container and create a level, even surface. Do not tamp down or overfill and compress the mix before planting the seed. Remember, the seed needs air spaces in the soil to breathe.
Most seed needs to be planted to a depth of 2 to 3 times its own diameter. A pea, for instance, which is 1/4 inch across, should be planted 1/2 to 3/4 of an inch deep in the soil. Smaller seeds can be sprinkled on the soil surface. Cover the smaller seeds with a fine layer of mix and tamp gently with the flat of the hand.
Keep the soil moist (not wet) and cover the container with a loose fitting plastic to help retain moisture. The best way to maintain consistent moisture in seed beds is by watering from the bottom. Place containers in a shallow tray of water filled approximately 1/4 to 1/2 inch deep with clean water. The seedling mix will draw the water up into the container and you will not have to worry about washing the seed out by top watering.
Vegetable produce bags from the grocer work very well as they are thin and can be left open at one end. Slide the container into the bag sideways.
Once the sprouts come up through the surface, remove any plastic covering. Watch for the first two leaves to appear, as this is your signal that it’s time to give your new little sprout a little compost tea or diluted liquid plant food.
Be very careful not to burn or overfeed it: remember, it is still a baby. Just as you wouldn’t’ give a newborn a steak, don’t give your baby plant a full adult plant size meal or it will very likely die from the shock.
6. Provide Seedlings with Stimulation and Adequate Light for Strong Stems and Healthy Plants
If you are sprouting seeds indoors or in a greenhouse, they will need some stimulation to grow strong stems. You can achieve this by either setting up a small fan to move the air over them or by gently brushing over them with your hand a few times a day. This will help prevent the seedlings from becoming weak and ‘leggy’.
Now that they have sprouted, they also need good light. A sunny window sill on the south side of the house, or a sunny outdoor spot during the day will work fine. Be sure to bring seedlings indoors at night if it is still before your last frost date or the nights are still chilly. By gradually introducing the seedlings to the cooler outdoor temperatures over a series of days they will be adequately prepared for going in to the garden.
Vegetables with larger seeds, peas, beans, corn, squash, melons, peppers, eggplants, and tomatoes are all very easy to germinate using this method, and can be sown directly into the garden once sprouted. To do this, make up a 2 to 3 inch ball of good potting soil or seed starter mix and place the newly sprouted seed inside the center of the ball. Then prepare your spot in the garden and place the ball of soil with its spouted seed into the garden and gently cover it with soil.
Birds are very clever and will happily spend a morning watching you plant new seeds and then spend their afternoon eating those seeds right out of your garden! This is especially true of blue jays.
Smaller seeded vegetables, such as celery, carrots and herbs can be a little trickier to handle and harder to see and work with; but the benefits can be just as dramatic, if not more so. Many of these seeds take longer to germinate and this method can reduce that time by as much as two to three weeks.
Finally, remember that new seedlings require the same consistency to thrive as they did during germination. Keep seedlings protected from strong winds, extreme temperature changes. Provide adequate light without letting them get too hot or dry.
Once your seedlings have developed their first ‘true leaves’ which are the leaves which can be identified as the plant and not the seedling starter leaves, they can start to be prepared for planting in the garden. Always give young seedlings a few days of outdoor exposure and return them to the indoors at night before planting them out into the garden. This gives them the opportunity to adjust to the new conditions of the outdoors before they are transplanted.
After the plants are hardened off, plant them into the garden during cool morning hours on an overcast day for best results. Hot sunny weather can be too hard on transplants in the first day; so if the weather is hot and sunny consider transplanting in the evening to give the new plants time to adjust to the transplant before exposure to a day of hot sun.