Soaking seeds before sowing is an old-time gardener's trick that you may not know about! It's a common practice among gardeners and farmers that can help to improve the chances of successful germination and even improve overall plant growth!
Seeds can be delicate and complex living organisms, and providing them with the ideal conditions for growth is key to a healthy and productive crop.
Soaking seeds in water for a period of time before planting can help to soften the seed coat, speed up germination, increase the germination rate, and identify viable seeds from non-viable ones.
You might be wondering if this is truly worth the time, and if so exactly how to soak seeds before sowing. In this article, I'll share the top 7 reasons why you should consider sowing seeds before germinating, along with which seeds to soak and which ones you should avoid soaking.
I'll also share my step-by-step guide to properly soaking seeds before sowing for the best results!
Is Soaking Seeds Before Sowing Necessary?
Let's start with the first question. Is soaking seeds before sowing necessary?
The answer is, no, you don't technically need to soak the seeds before sowing, but it sure does speed up germination big time.
We are all aware that seeds in the wild can germinate without our assistance. Throughout hundreds of thousands of years, they adapted to reproduce without the attention often given by home gardeners.
That means you don't need to do this extra step to be successful when you plant seeds. Plant seeds in trays or directly into the soil, give them a good soaking and watch for the sprouts to appear.
But, there are many advantages to soaking that make it worthwhile.
Even though you can grow some plants from seeds that haven't been soaked, your chances of success and the speed of growth will be much better if you do.
If done properly, it can increase the germination rate from a few percent to nearly that of the entire batch of seeds. That not only saves you money in the long term but a ton of hassle too!
7 Reasons To Consider Soaking Seeds Before Sowing
There are 7 main reasons why I recommend you consider soaking seeds before planting them. Let's check them out in more detail:
1. It Triggers Germination
Seeds, as we all know, require moisture to germinate. Depending on how much rain falls in their natural environments, various seeds have varied moisture thresholds at which are they triggered to germinate.
The plant understands it is safe to start germination once the rainfall has increased the moisture around the seed to an acceptable level.
By soaking the seeds before sowing, you can activate and trigger this moisture sensor in any seed to promote germination. You don't have to wait for your seed starting mix to bring them to that stage, which could take a lot longer.
Instead, by soaking seeds before sowing, they won't need anything more than a planting to get going.
2. It Helps Speed Up Germination
By starting the germination process before you put the seeds in the ground (or in trays), you can cut down on the time it takes for your seeds to go from sowing to being ready to be transplanted. Your seeds should germinate quickly because there is no moisture barrier to overcome.
Room-temperature water also helps to accelerate this process. Seeds need a certain amount of water before they can grow, and they also have sensors that can tell when the temperature is too hot or too cold. These sensors prevent the seeds from germinating when the temperature is too low, so protecting the tender new growth from damage.
Room temperature water offers the ideal conditions for rapid germination because it is at the same temperature as the seeds. You should expect much faster results from your seed-starting efforts if you use this method in combination with a heating mat to keep the soil warm. This can be particularly when starting seeds early.
This is also ideal for planting in the late season since it provides you with that extra push when time is running out so you can plant your seedlings before it's too late.
3. It Removes Germination Inhibitors
Although it may appear contradictory, some seeds are actually surrounded by germination inhibitors. Mother nature is incredible, and the reason this is the way is because it keeps them from germinating inside the fruit at the wrong time.
Most of the time, wind or rain will remove these inhibitors on their own, but this can take a while. You can improve your chances of successful seed germination by soaking them first.
4. Break Down Natural Defenses
Seeds are used to being knocked around and disturbed before they end up in their final place. Before they sprout, seeds are used to being tossed around by the wind, getting pelted by rain, or surviving stomach acid from animals that eat them.
Many seeds have tough shells that protect them from these things. Instead of waiting for Mother Nature to do so over the course of days or weeks, you can speed up the process by soaking your seeds to remove these barriers in only a few hours.
They will be completely ready for sowing after a good soak.
5. Helps Identify Viable Seeds
Soaking seeds can also help you identify viable seeds from non-viable ones. Seeds that sink to the bottom of the container during soaking are more likely to be viable, while those that float are likely to be non-viable.
The reason for this is that viable seeds have a healthy and intact embryo inside, which makes them denser and causes them to sink. In contrast, non-viable seeds may have a damaged embryo or may have dried out, which makes them less dense and more likely to float.
By identifying which seeds are viable and which are not, you can save time and effort by only planting seeds that are more likely to germinate and grow into healthy plants. This can be particularly important if you are working with limited seeds or growing in a challenging environment.
It's worth noting that while seed viability can be indicated by whether they float or sink during soaking, it's not always a foolproof method. Some seeds may still be viable even if they float, and some may not be viable even if they sink. However, it can be a useful preliminary test before planting to help increase your chances of success.
6. Overall Increases Your Chances of Success
Each year, plants all around the world produce billions of seeds. But, because of the many problems we talked about before, not all of them will sprout.
They scatter so many seeds with the hope that a few would germinate. This helps because this way they can successfully reproduce but it also means that not all seeds will germinate.
If you bought rare or expensive seeds, or even just regular seeds, you can't just count on luck to make them grow.
While it is possible for seeds to germinate without being soaked, doing so significantly improves success rates. This extra step is well worth it if you want more reliable results.
7. Helps Soften Seed Coat
Soaking seeds before sowing can help soften the seed coat, making it easier for the seed to germinate and grow. This is particularly important for seeds with a hard seed coat, which can make it difficult for water and air to penetrate and for the embryo to emerge.
When a seed is planted, the seed coat acts as a protective barrier that helps keep the embryo inside safe from external threats.
However, this same protective layer can also hinder germination if it is too thick or hard. Soaking the seed before planting can help to overcome this barrier by allowing water to penetrate the seed coat and trigger the process of germination.
Soaking the seeds in water for a period of time can also help to leach out any natural inhibitors or growth-inhibiting chemicals that may be present in the seed coat. These inhibitors can prevent the seed from germinating, and by removing them, the seed is more likely to sprout and grow.
In addition to softening the seed coat, soaking seeds can also help to hydrate the embryo inside, providing it with the necessary moisture to begin the process of germination. This can be particularly important if the soil conditions are dry, as it can give the seed a head start in establishing itself and growing roots.
Overall, soaking seeds before sowing can be an effective way to overcome the barriers presented by a hard seed coat and increase the chances of successful germination and plant growth.
However, it's important to note that not all seeds require soaking, and some may even be damaged by it, so always keep reading to find out which seeds you should consider soaking and which ones don't require this extra gardening step.
Which Seeds Are Suitable For Soaking?
As a general rule of thumb, you don't need to soak smaller seeds, but you do need to soak larger seeds with hard shells. Overcrowding can occur when small seeds clump together after soaking and are later difficult to separate.
Bigger or harder-shelled seeds are often the most difficult to germinate and should be soaked before sowing. Here are some of the most common ones:
Apart from these, the majority of other thick-coated medium to large vegetable and flower seeds benefit from soaking before sowing.
Other things you can consider soaking are garlic cloves and even onion sets to speed up the germination process before you plant them outside in your garden
Seeds You Shouldn’t Soak Before Sowing
When some little seeds are soaked, they become difficult to handle and spread out. It is important to avoid from soaking the following seeds before planting them:
Zinnias, in particular, start to germinate at the first sign of any kind of moisture so they don't need soaking before sowing at all.
Soaking will greatly increase your germination rates and the speed of the process.
But, after planting, seed care is still important. Make sure you keep the soil moist and the tray warm enough to continue the hard work you put in in the beginning.
How to Start Soaking Seeds Before Sowing
Now that we've covered all the basics, let's look at exactly how to soak seeds before sowing:
Supplies You'll Need
- Room temperature water
- Small clean container
How to Soak Seeds Before Planting (Step-by-Step)
Start by placing the seeds you're planning to plant into a small, clean container, bowl, or jar.
Next, fill the container halfway with room-temperature water. Leave the container in a warm spot for a minimum of 8 hours, but for the best results, you should do it for up to 24 hours before planting. However, keep in mind that too much soaking in water will drown the seeds and they will start to decompose.
You might come across a few floaters that you should consider tossing away since most of the time they will not germinate, as I explained above.
Once your seeds have puffed up, plant them immediately into moist soil
After soaking, plant your seeds immediately into moist soil. If the seeds are allowed to dry out after being soaked, they will most likely not germinate. To prevent wasting the effort of soaking, keep the soil moist until the seeds have fully germinated.
Guide to Soaking Seeds Before Sowing & Why You Should Do It
- Vegetable Seeds - Seeds that are looking more like grain can be soaked like tomato cucumber, pumpkin, squash, zucchini, peas, beans, etc... But seeds like radish, dill, carrots I do not soak in water as it will be impossible to plant them.
- Water - room temperature water is best for soaking seeds.
How to Soak Seeds Before Planting (Step-by-Step)
- Start by placing the seeds you're planning to plant into a small, clean container, bowl, or jar.
- Next, fill the container halfway with room-temperature water. Leave the container in a warm spot for a minimum of 8 hours, but for the best results, you should do it for up to 24 hours before planting. However, keep in mind that too much soaking in water will drown the seeds and they will start to decompose.
- You might come across a few floaters that you should consider tossing away since most of the time they will not germinate, as I explained above.
- Once your seeds have puffed up, plant them immediately into moist soil
- After soaking, plant your seeds immediately into moist soil. If the seeds are allowed to dry out after being soaked, they will most likely not germinate. To prevent wasting the effort of soaking, keep the soil moist until the seeds have fully germinated.