What number of seeds does it take to develop a plant?

If you are planning for the upcoming season, you may want to start with seeds indoors. Perhaps you have trays and starter pots and are planning on planting multiple seeds. But you may be wondering, "How many seeds does it take to grow a plant?"

That's a good question, and the answer is many. So many different considerations come into play when getting seeds to grow plants. Different gardeners have different answers. There are several factors that come into play. And not every seed is the same in fitness.

Before you start planting these seeds, let's cover some of the basics that will determine the number of seeds you will need to grow your garden plants. We'll look at different types of seeds and how they differ from each other. We'll also cover some techniques that will get your seed starting game in a nutshell.

What is a germination rate?

How many seeds does it take to grow a plant? Let's explore that! Source: Melanie O

Some gardeners may keep encountering the problem of not having enough sprouts. This could be due to their tendency to only plant one seed per plant and only end up with as many plants as they'd like.

One of the basic things to consider when planting multiple seeds is the germination rate (check your seed package for this). Germination rate refers to the percentage of seeds that sprout into plants out of 100. So if you have a 90% germination rate, 90 out of 100 seeds will likely germinate if all the basic conditions are met.

The basic conditions include growing seedlings in a warm environment that leads to germination. You need a light and good starter soil for the seeds. A heating mat delivers optimal results. On the other hand, you could even start in a greenhouse.

In terms of germination rate, you want to plant with your plants for optimal success. Instead of thinking about the number of starter pots, think about how many holes you are going to make in the earth. List that and compare that to the germination rate. Chances are, you should plant at least two seeds per hole.

But you don't want to overdo and overproduce here just to run out of space for your seedlings. You also don't want to be overwhelmed by the number of plants you have, even if you have the space. Remember, you can save seeds and grow the same plants the following season.

On the other hand, you don't want to just plant one seed per plant. When you have optimal conditions for your seeds to sprout, look at the germination rate to determine how to plant. Sometimes the germination rate is present on packets of seeds. Sometimes you have to dig a little. Also, keep in mind that fresh seeds are more successful than older seeds.

Once the germination rate matches the number of seeds per hole, starting seeds indoors is a breeze.

Germination rate formula

Once you find the germination rate, follow this formula to determine how many seeds will fit in the same hole. Then start planting seeds. Note that this formula will only work perfectly in a controlled environment.

It is likely that the rate of sprouts you are observing is not exactly the same as the rate. The rate gives you a baseline of how many seeds to plant per hole.

Number of holes x germination rate = number of plants

Let's start with 72 holes and one seed each with a germination rate of 70%. You would multiply 72 by 80% and get about 57 rungs. In this case, you can plant 2 to 3 seeds per hole and you will likely have maximum success.

You will find that often you need to plant more seeds than there are holes. 2-3 seeds per hole is a good starting point, but you could be wasting seeds doing this. Let's cover some of the subtleties involved in starting seeds. This way you will have extra seeds for the next season.

Seed size and germination

Sowing in pellet bowlGerminated seeds in pellet trays must necessarily be diluted. Source: Rachael & Zane Ross

Cucumbers, pumpkins, melons, and squash have high success rates. This is because larger seeds generally have higher germination rates due to greater fitness. It may not be worth planting two to three seeds per hole here. However, if you have already sprouted two seeds in the same hole, just dilute them.

Plants with tiny seeds, like lettuce, tend to germinate more slowly. Often times, you will be more successful with these seeds if several are planted in one hole. Plant double the amount of lettuce seeds compared to the above.

How many seeds to plant

Seed size isn't the only factor that determines germination rate. The condition of the planting area is one thing to consider. The decisive factor is the type of plant. Different plants have different germination rates. And you'll want to make room for mistakes or losses as you toughen up. Often a single seed is not enough to produce a healthy plant.

Fruits, vegetables and cereals

Tomatoes have medium-sized seeds that have a very high percentage (around 98% on average). In this case, you can plant 1 to 2 seeds per hole and thin out plants as needed after they sprout. Part of the reason tomatoes are so popular with gardeners has to do with the ease with which they can be grown from seeds. As long as you have a good seed starting mix, you can succeed with individually planted tomato seeds.

Giant onion seeds are medium in size and have a hard shell. But giant onion seeds also have a high success rate, especially when they are fresh. In this case, the rule of 2 to 3 seeds per hole applies. Because onions grow in a myriad of conditions, if you're less successful than you'd like in a growing season, you can sow more seeds later.

There's a reason people don't sprout berry seeds often: they often have success rates of 50% and below. A single seed or just a few seeds will not turn into small plants as easily. For berry plants, plant several seeds per hole. Note that you will have a lot less success here than with larger seeds.

Collard greens also have a pretty high success rate and can easily sprout with 2 or even 1 seed per hole. More than one seed gives you more success and more to work with after hardening. If you are working in a pot, try planting in a few different parts of a pot.

Regardless of the germination rate, it is recommended to only plant 3 rice seeds or less per hole. This is because large seeds like rice can experience stress during the transplant process if there are too many sprouts in one hole. So don't plant a whole bunch of rice right away.


One flower that I've found sprout very easily is marigold. These seeds look a lot like mealworms with their twisted shells. About 78% of them germinate. The same goes for borage seeds. And both types of seeds are roughly the same size to medium in size.

Chamomile is one of those flowers, the tiny seed of which depends on numerous factors to sprout successfully. Many people I know (myself included) have major problems with chamomile because, while the success rate of the seeds on the package is high, other problems such as too much moisture or too fertile soil can make gardening difficult with them. You may need to use a large number of seeds to grow a chamomile.

Some smaller plants like lupine and alyssum will self-seed in the garden and don't need any help. With self-seeding plants, just let them do their thing in the garden and avoid starting with self-mixed soil.

Littered parsley seedsParsley and other herbs can easily be seeded and thinned out. Source: Satrina0


When planting herbs from seeds, you must know that you will need to plant several, and you need to be patient. Gardening with mint, tansy, dill, and parsley is very rewarding, but you should plant several seeds of each type per hole.

For example, I grew a white sage plant from seeds but had to feed almost all of the seeds I had into the ground before I could germinate it. The germination success rate for this plant was about 40%. Had I failed to plant more than one seed, my chances of being lucky at all would have been slim. However, this is an extreme case. Most herbs have a higher rate, but the rate will generally be lower than that of watermelon, for example.

DIY projects like building your own herb garden feel a lot better if you start over and continue to the end. Why not try the rewarding process of a herb garden from scratch?

Thin out seedlings

If you've planted two seeds in one hole and they both sprout, what now? Well, choose the healthiest of the two and remove the other. Use small scissors to cut the sprout planted in the starter pot rather than pulling it out and disturbing the roots of the plant you have chosen. It may seem like a waste, but the roots of the eliminated plant will collapse and supply the other with nutrients.

frequently asked Questions

Seed startedOnce you've started your seeds, you'll see germination rates in action. Source: Satrina0

Q: How long does it take for a seed to grow into a plant?

A: It depends on the plant. There are a few general rules. Larger seeds will sprout more easily, while smaller seeds will grow less successfully. Fresh seeds are more voracious than old ones.

Q: Can you put seeds directly into the soil?

A: Yes, but in this case you have a lot more to do. Seedlings exposed to the elements can be flooded, eaten, burned, etc. Unless the plant is better sown outdoors, try starting yourself.

Q: Which seeds germinate the fastest?

A: Brassicas and salads sprout the fastest of all seeds. Beets and radishes also grow quickly.

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