Updated/Fact-Chacked on March 9, 2022 by John
Whether you are planting a new flower bed, adding to an existing garden area or starting seeds for your vegetable garden, it is often helpful to give the seeds a little jump-start by soaking them (aka priming them) before planting.
Even though seeds can germinate without being soaked, soaking them overnight gives them a head start. This results in faster sprouting and growth.
Whether your seeds are sown in multi-purpose compost or sown in a seed compost, we recommend soaking them before sowing them to speed up germination and to make it easier for the young seedlings to establish.
Seed soaking (aka pre-treatment or priming) has been shown to significantly improve speed of germination and biomass production especially in adverse conditions such as stress from high temperature, salinity, and low nutrient conditions.
Why Do Seeds Need To Be Soaked?
For most plants, their seeds are made difficult to germinate on purpose by nature. It doesn’t want every seed to sprout right after it falls to the ground. It is a matter of survival.
In nature, it can often take several rain showers for a seed to become soft and swollen enough for the tender radicle or root tip to push through the hard outer coating and crack open the seed coat. Soaking seeds before planting gives them the same effect as that rainfall.
Soaking your seeds before you plant them helps to hydrate the seeds, which softens the protective seed coating. Most of the time this helps the tiny root start to grow inside before it even comes in contact with soil, giving the seed a better chance of germinating. Soaking also helps speed up germination time.
A soaking is great for many of the more common seeds like tomato, pepper and squash that have hard seed coats. It’s a good way to get an extra boost of moisture to them before they sprout.
Soaking seeds can also reduce the chances of “damping off,” a disease that causes seedlings to fall over and die just after sprouting. Damping-off is caused by a fungus that can be introduced with soil or by coming in contact with other diseased plants. It is especially important for slow-sprouting, hard-coated seeds to take a dip before planting.
How to Soak Your Seeds
Here are a few tips on how to soak your seeds before planting.
- Before planting your seeds, soak them in warm water at room temperature for 24 hours to soften their hard outer shells.
- Some large or hardy seeds may require a little longer; read the instructions on your seed packet for details.
- Gardeners can soak seeds in 2 parts water and 1 part hydrogen peroxide, which is actually good for plants because it helps provide oxygen to their roots. Other gardeners add a pinch of epsom salts.
- After 24 hours, drain the seeds and you can then plant them directly into the ground (if you’re planting outdoors), or into a seed tray (if you’re sowing indoors).
Soaking seeds gives them a head start in life and if you are a keen gardener, it is well worth the small amount og time and effort to get better and healthier plants.
Related Seed Articles
>> How long does it take for a seed to germinate?
>> How to start seeds in a paper towel
>> 10 steps to grow plants from seed
>> How to speed up seed germination
>> Will grass seed grow if just thrown on ground?
>> Heated seed propagator buying guide
>> Seed compost v multi-purpose compost
>> Should you soak seeds before sowing?
John Green is a 46-year-old graphic designer living in Durham. John is RHS level 3 certified and owns an allotment in Durham.