*Hot Soak - you can break seed dormancy much quicker with some species if the seeds are exposed to hot water. We usually place these seeds in about a cup of 180o F water (80 o C) and let them soak (and cool) overnight before planting.
Temperature influences the moisture content, hormone function, and enzyme activity that occurs during seed germination. Warm temperatures accelerate the chemical reactions in seeds and accelerate cell formation for development.
Speed Up Germination
Using warm water also helps speed up this process. While they have moisture levels that need to be met before they can germinate, seeds also have temperature sensors. These prevent the seeds from germinating when it is still too cold, risking damage to the new and vulnerable growth.
This method could be the fastest way to germinate seeds. Place seeds in a shallow container in warm water and leave them for 16 to 24 hours (smaller for 16, bigger for 24). Remember not to expose seeds to temperatures higher than 80°F (26.6°C) and not to pre-soak seeds for more than 24 hours.
For seeds to germinate, you need to keep the growing soil damp but not too wet. Learning how to water seedlings is pivotal for success. Many seed starters cover the container to keep soil moist until seeds germinate. Once seeds sprout, do not miss a watering.
The majority of seeds grow most effectively in the dark. Light, which is essential for seedling growth, may actually hinder the germination process. The three primary and necessary conditions for a seed to germinate are water, oxygen, and temperature. Thus, Light is not necessary for a seed to germinate.
The seeds you shouldn't soak include: carrots, lettuce, radish, celery, turnips, and spinach. Listen to Cathy Isom's This Land of Ours program here.
Too much soaking in water and a seed will drown. It is recommended that you only soak most seeds for 12 to 24 hours and no more than 48 hours. The seeds of some species of plants can survive longer soakings, but you should only do this if the specific instructions for this species recommend so.
All seeds need water, oxygen, and proper temperature in order to germinate. Some seeds require proper light also. Some germinate better in full light while others require darkness to germinate.
Many factors affect seed germination, but the most challenging for gardeners and often least understood is soil temperature. While there is can be variation from one seed type to the next, most seeds for warm-season edibles prefer soil temperature between 70 and 80 degrees Fahrenheit (21.1 and 26.7 Celsius).
Suffice it to say that it is mainly the light's effect upon a plant pigment called phytochrome within the seed. This relates to the type of light which the seed receives. As a generalisation, light in the red wave length usually promotes germination whereas blue light inhibits it.
Most of the seeds germinate best in dark environments. The presence of light tends to inhibit their growth. The light decomposes carbonic acid gas and expels oxygen which leads the seed to harden. These gases are key factors that promote germination.
Soaking your seeds in hot water held to a specific temperature will also break down the seed coating. But this one is a double-edged sword. Soaking seeds in hot water will help speed up germination but can come at the cost of lower germination rates.
Paper towels, filter paper or even newspaper provides an excellent medium for germinating seeds. They are pathogen-free and make it easy to control the moisture content for proper germination. This method also takes the guesswork out of knowing if your seeds have germinated since you can easily observe them.
Vinegar is an aqueous solution of acetic acid, which inhibits the process of seed germination. Higher concentration of acetic acid may destroy the seed vigor and inhibit the germination of seeds. Overall, vinegar can kill the seeds, the leaf, and possibly the entire plant.
Make sure to strain and rinse the nuts or seeds after soaking to eliminate the residual water which contains the absorbed enzyme inhibitors and toxic substances. Once you have given them a good rinse, enjoy them immediately or store them in your refrigerator for later.
Some seeds take a long time to germinate, and seed soaking can help to speed up the process. By soaking seeds in lukewarm water for 8-12 hours (some can go up to 24 hours, but never more than that), you help the seed to break dormancy and germinate faster. Place the seeds in a shallow bowl near a window.
Seeds are self-contained systems that contain most of what they need to get themselves started, but there are three important triggers that kick off germination: air, water, and warmth.
Seeds need to be moderately moist to sprout. Seed germination is highly dependent on watering. Too dry and they won't get the message to sprout, too wet and they will rot in the dirt.
Some are quick to germinate, taking 1-2 weeks at most, such as chillies, beans, sunflowers and pumpkins. Some seeds take more like 2-4 weeks, such as mango and parsley. Others, depending on how warm/cold it is, take closer to 2 months, for example avocado.
Many variables can affect the germination rate of seeds. How the seeds were stored, their age, the depth at which they were planted, the weather, the soil they were planted in, moisture, and temperature can all play a role in the success or failure of germination.
Until seeds have sprouted, keep the seed bed moist, never allowing it to dry out. Water with a fine-spray hose nozzle or watering can which will provide a fine misty spray and not wash away the soil. Water often enough (usually about once a day) so that the soil surface never dries out, but remains constantly moist.
Like most things in gardening, there are always exceptions to this rule of 2-3 seeds per hole. If you're planting large seeds like cucumbers, melons, or pumpkins, you should only use one seed per hole. However, you can still plant seeds close together and then thin them out once they've established themselves.