best soil mix for starting seeds

The 8 Best Seed Starting Mix in 2020 – (Reviews & Guide)

Most people know that plants grow when the conditions are favorable. You may have weeds all over the place. However, when it comes to sowing seeds, you need the right tools.

Your seeds need the optimum growing mediums to germinate and grow. Finding the best seed starting mix is ideal here. We take a look at some of the top products and help you choose the right one based on your needs.

Of course, we also answer some common questions. That way, you are prepared to germinate seeds successfully each year.

Table of Contents

What Is Seed Starting Mix?

The seed starting mix is sometimes called seed starting soil. The terms are used interchangeably, and they mean the same thing. However, the word ‘soil’ is misleading because it’s not the same as potting soil.

Seed starting mix doesn’t have a lot of nutrients. In fact, it’s as low as it possibly can be. Generally, it is designed for a specific type of plant and has controlled nutrients intended for them.

Usually, it contains no soil at all and is only there to help the seed germinate. It’s typically lighter and finer than soil, so the tiny seeds can grow into seedlings more easily.

While seeds do need plenty of water, they can rot if they stay wet for too long. Therefore, the seed starting mix holds onto the water, but it doesn’t stay soggy. This is the ideal environment for your seeds.

Seedlings don’t need soil because they get their nutrients from the seed itself for the first few weeks. Compost is often included in the starting mix, which feeds the seeds while they grow.

Soil also contains fungi and can develop mold, neither of which your seed needs. When you choose a mix without soil, you reduce the risk of rot or bacterial infections.

Seed Starting Mix vs. Potting Soil

Beginner gardeners don’t often understand the differences between potting soil, garden soil, and seed starting mixes. However, there are distinctions between them.

This can kill or breathe new life into your plants, so you should be aware of all three options and how to use them correctly.

Gardening Soil

Gardening soil usually has topsoil, which is mixed with fertilizer, compost, and other things. It’s designed to be used in garden beds only. Some mixes also feature microbes, which can help your plants grow better.

Generally, it’s the base soil for the garden. Each region features a different type of base soil with various minerals, clay, sand, and silt.

You shouldn’t use gardening soil to start your seeds. They need a special mix that can give them the right nutrients without killing them. Garden soil is often heavy and compacts down too much for the seed to sprout.

This essentially smothers the seed’s roots. You’ve also got larger chunks, which makes it hard for the seed to break the surface.

Potting Soil

Potting soil is designed for plants that grow in containers and pots. It is lighter than traditional gardening soil because it contains perlite and other substances. Still, there are going to be organic matter chunks, such as bark fines.

They are beneficial for regular plants, but not good for the smaller seed cells. Often, seeds find it hard to get through to the surface, dying before they reach the air.

However, some potting mixes can also be used as a seeding starting mix. It often tells you that on the package label.

Seed Starting Mix

As the name suggests, the seed starting mix is designed to start the seeds off so that they grow. It’s incredibly light and fine-grained. This promotes root growth and doesn’t compact around the seed in the container.

Though you can make your own, it can still be costly for the ingredients. Plus, it is messy, and you might not get the right ratio of ingredients. Instead, it is best to use a commercially made seed starting mix because it has everything you need.

The 8 Best Seed Starting Mixes for Vegetables & Garden Plants

We are going to discuss eight different seed starting mixes that work well for plants and vegetables. See a list of them below in the table.

Pictures Seed Starting Mixes Sizes Links
Miracle-Gro 74978500 Seed Starting Potting Mix 8 qt
Espoma Organic Seed Starter Premium Potting Mix 8 qt, 16 qt
Black Gold 1311002 Seedling Mix 16 qt
Burpee Organic Coir Compressed Seed Starting Mix 8 qt
Jiffy Natural & Organic Starter Mix 10 qt
Purple Cow Organics Seed Starter Mix 12 qt
Gardener’s Supply Company Seed Starting Mix 9 qt
Coast of Maine Organic Seed Starter 16 qt

Best Seed Starting Mix Reviews

1. Miracle-Gro 74978500 Seed Starting Potting Mix

If you’re looking for an excellent product to start your seeds off right, Miracle-Gro is always a top choice. The brand is very well known, so you can expect it to help your seeds grow big and strong.

This product is formulated specifically to help the roots grow and develop quickly. It’s also enriched with plant food designed by Miracle-Gro.

You should use this product when you’re putting the seeds in small containers. It works best for this situation. Plus, it can be used to start your cuttings.

Consider using this product for root cuttings, stem cuttings, and leaf cuttings, as well. This seed starting mix is ready to use out of the bag. That means you just pour it into the containers, put the seeds in, and water it.

When you have a lot of seeds to grow, you may choose to buy the two-pack version of the product. One bag of the Miracle-Gro brand can grow up to 32 seeds.

2. Espoma Organic Seed Starter Premium Potting Mix

Everyone seems to want to go organic, and Espoma offers a seed starting mix to help you. Start your seeds off right so that they grow in a natural environment without any chemicals.

This product is designed for all cuttings and seedlings. You get an all-natural product that is enhanced with myco-tone. This is the Espoma’s proprietary mycorrhizae blend.

Myco-tone can improve growth and help with transplant survival rates. You are also going to get bigger roots from the plants, which promotes more water intake. Plus, this blend can help boost tolerance of environmental stresses that your plants may face at times.

You can purchase this product singularly, as a two-pack, three-pack, or four-pack. It’s also available as a 16-quart or 8-quart version.

The bags come sealed, and you must rip off the tops. It isn’t designed to be stored in the bag. You may save it for a short period of time in a separate container with a tightly sealed lid.

3. Black Gold 1311002 Seedling Mix

The Black Gold brand is well-known and offers a seedling mix, as well. It is a full 16 quarts, but it also comes in a two-pack or four-pack. Therefore, if you’ve got many seeds to grow, you can buy in bulk.

This mixture contains Canadian Peat Moss, as well as other ingredients. That allows the seeds to have appropriate moisture and aeration for strong root development.

You are going to find that this product is organic and listed by the review institute. It’s also made in America. Of course, it is suitable for root growth and can help germinated seedlings grow quickly.

The other ingredients include dolomite lime, perlite, and a wetting agent, which is organic. You can use this product to germinate seeds in plug trays, pots, or flats. Most people choose flats or trays because it is easier, but you can utilize the option that meets your needs and is readily available where you live.

4. Burpee Organic Coir Compressed Seed Starting Mix

Do you want to try something a little different? If so, then the seed starting mix from Burpee might be ideal. It’s organic, but it is also compressed into a brick shape.

This mixture is fully biodegradable. Plus, it is made using coconut coir. You are going to find that this renewable resource is produced primarily by recycling the coconut husks once they are harvested.

Of course, you can use it as a growing medium for almost any plant out there. You get one brick.

Put it in a container and water it. The compressed brick is going to expand in mere minutes to 8 quarts of seed starting mix.

Since it is listed as organic, it is on the OMRI list, as well. Therefore, you can be sure that it is safe for organic gardening.

You are going to get your hands dirty because, as the brick expands, you need to break it up. Gloves might be suitable for this step.

5. Jiffy Natural & Organic Starter Mix

Jiffy has come out with an organic and natural seed starting mix. It’s designed to be of greenhouse quality and is completely organic.

Like many other starter mixes, this one contains lime, vermiculite, and peat moss. The peat moss holds about 20 times its weight with water. It can also ensure proper aeration and retains nutrients for the plants.

Vermiculite is there to prevent the soil from compacting. It soaks up about three times its volume with water. Therefore, if there’s too much liquid, this can wick some of it away from the seed so that it doesn’t rot.

Lime is also included, which helps with the pH balance for your soil. Wood bits are also there, which can help reduce soil compaction, as well.

It comes in a 10-quart bag, which is enough to start 32 seeds. You are also going to find that the bag is resealable. Therefore, you can close it up and use it again on a different day.

6. Purple Cow Organics Seed Starter Mix

Purple Cow is not a well-known brand. However, its seed starter mix is fully organic, and OMRI listed. The mixture contains activated compost, mineral complexes, and granular fertilizer, which is also natural.

That way, your seeds get off to the best start possible. This product is designed to be used in small containers, blocks, or trays and should only be used to start the seeds.

There is wicking action involved here, which keeps the roots moist without waterlogging them. The mixture doesn’t get compacted, which means there is enough drainage. Also, this allows the seeds to grow roots and pop up from the surface.

The ingredients include Sphagnum peat moss, Purple Cow compost, Vermiculite, Perlite, fertilizer (OMRI listed), and sea/rock minerals. You are going to see many benefits from this product.

Of course, the seedlings are going to be sturdier for transplanting. Plus, the plants are going to be upright, so they are healthier.

7. Gardener’s Supply Company Seed Starting Mix

The brand Gardener’s Supply Company isn’t well known, but it does have a seed starting mix you might like. It features MycoActive and SuperRoot Booster technology. This creates a living mixture of soil so that the seeds and thrive and plants survive.

It contains mycorrhizae, which are incredible microbes. They form partnerships with the root system to support resilient and vigorous plant growth.

The SuperRoot Booster is designed to provide more nutrients and boost water uptake. The plants are going to be more resistant to stress and tolerate drought better, as well.

This product is a blend of finely-textured ingredients. You can use it in regular seed starting trays. However, it can also be poured into self-watering trays.

Therefore, you can do less work and still have seeds that sprout and become beautiful, healthy plants. Plus, it offers balance for draining and wicking moisture away from the plants, as well.

8. Coast of Maine Organic Seed Starter

The Coast of Maine brand is organic, and it’s designed for starting seeds. You can use it for rooting plant cuttings and seed germination.

This product is ready to use. Plus, you can utilize it in flats, trays, and cell packs. Therefore, it’s possible to use it with whatever you already have around the house or whatever is least expensive in your region.

With worm castings included, you are going to get more aeration and natural moisture retention. The nutrients included here are mycorrhizae, fully cured compost, and kelp.

The company recommends that you use 72-count cell packs or bigger. There are 16 quarts (dry) of the product, so that is plenty. However, you can buy extra if you are worried that it might not be enough.

Called the Sprout Island Blend, it’s ready-to-use and organic. The kelp and worm castings are there to create a slight fertilizer charge. It’s also the best biological environment for your sprouts.

How to Use Seed Starting Mix?

The way you use seed starting mix is always the same. However, you may have to do something to the product first. For example, the brick variety requires enough water to turn the brick into the mixture.

You should follow the directions for using the mixture, which is on the back of the package. However, most of them are similar in structure.

Usually, you wet the mixture using warm or lukewarm water first. It should be moist, but it should not be sopping wet. There shouldn’t be any dry areas, but you don’t want it to look like mud.

Make sure that you’ve got the appropriate planting containers, such as trays or flats. Fill them each up, leaving the last ¼ inch free. Once they’re all filled, tap the whole flat gently to settle everything.

Read the directions on your seed packets to plant them in the starting mix. Water the seeds very lightly. Don’t saturate the full volume of the starting mix.

Recheck the seed packet directions for proper temperature conditions and lighting needs. Then, move the trays to the right location.

When they have germinated, you’re going to leave them in the starting mix and tray, giving them up to 14 hours of sunlight every day. You don’t want leggy growth, so you should keep them near to the light source as much as possible.

Once the seedlings are big enough, you can transplant them to containers or into the garden. Then, you are going to require regular potting soil.

Can You Reuse Seed Starting Mix?

No, it is not ideal to reuse your seed starting mix. This shocks a lot of gardeners.

You’ve used it for the full season and had excellent results. Why, then, shouldn’t you use it again and again?

For one, there could have been changes to the soil since it was first use. Now, it might be less suitable for your plants. Seed starting mix collects a lot of matter, such as leaves, roots, and more.

Plus, the plants are going to remove all of the nutrients from it. There may also be nematodes and insects that live in the mixture. Viruses and bacteria can even thrive here.

Keep in mind that some insects are good for the starting mix and plants. However, many of them are going to deplete the nutrients before the plant does. These pests might also eat the plant as it is trying to grow and thrive, which means you have done all that work for nothing.

Sometimes, parts of the root system are left behind. Though you take the ball of the roots, there could be stragglers. This is unhealthy for new seeds and can confuse them into not sprouting at all.

All of these issues could cause significant problems for you during the next growing season. While you can treat the seed starting mixture first, it’s often easier to dump that out and get new stuff.


When it comes to choosing the best seed starting mix, you had eight choices available. Though they all work well, we did find a clear winner.

The Miracle-Gro brand is so popular for a reason. It’s starting mix is designed for quick root development. Plus, it contains appropriate plant food that is going to help the plants later. Just make sure you’re wetting the mixture before adding the seeds for best results!

Those who want something a little more interesting might like the Burpee brand with its compressed mixture. Just add water, fluff up the mix, and follow the directions for using it!

Seed starting mix, potting soil or garden soil, what is good soil for starting seeds? Here, we reviewed the 8 best seed starting mix in 2020.

Make the Best Seed Starting Mix for Dirt Cheap (It’s Organic Too)

The best DIY seed starting mix needs only three ingredients, and you can find them all in your local garden center. Save money and get my no-fail recipes for organic seed starting mix and potting mix you can make at home.

When it comes to gardening, I’m all for getting started on a shoestring.

But where I feel I get the most value, especially if I’m starting hundreds of seeds (which isn’t hard to do in a season when you think about it) is in making my own seed starting mix.

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What is seed starting mix?

Go to a nursery and you’ll realize two things about seed starting mixes.

First, they’re relatively expensive. Sure, the price tag on a typical 8-quart bag doesn’t seem too bad, but then you bring it home and realize that 8 quarts isn’t really going to cut it when you have a whole flat of seeds to sow.

Second, some seed starting mixes contain chemical agents to hydrate the soil or supplements to supercharge your plants, which — for starting seeds — are completely unnecessary.

This is because all the nutrients that a seedling needs in its initial stage of life (before it develops its first true set of leaves) is contained in the seed. Think of it like an egg yolk for a baby chick.

A seed does not need fertilizer, compost, or beneficial microbes to germinate, nor does a seedling need any of that to grow healthy and strong in the first couple weeks. (You can read more about seed to seedling anatomy in this post — it’s truly amazing how self-contained seeds are.)

Soilless seed starting mixes should only contain three ingredients — and you read that right, soil is not one of them.

I remember being confused when I first learned about soilless mixes. How does a plant grow without soil?

It all comes down to starting seeds versus growing plants. In the beginning, seedlings just don’t have the same needs their grown-up selves do.

The best seed starting mix (which you’ll learn to DIY below) is made of perlite, vermiculite, and sphagnum peat moss.

This blend is made specifically for seed starting, and it’s very light and fine-grained to help promote baby root growth and ensure the mix doesn’t get compacted in seed starting cells or seed starting containers (which are usually only 1 to 3 inches in size — tiny!).

Is seed starting mix necessary?

You may be wondering why you need to use a soilless seed starting mix when you normally just plant your seeds in the garden, straight in the soil.

Here’s the thing: Garden soil has the advantage of being in the ground and living in harmony with the soil food web. It’s ideally well-draining and somewhat forgiving, as you tend to let Mother Nature take over and aren’t as obsessed over what does or doesn’t take off.

Unfortunately, garden soil tends to be too dense for seed starting and potting. It’s full of weed seeds. It’s teeming with microbes (both good and bad) and because they’re now constrained in an indoor environment without natural checks and balances, they can wreak havoc on your seedlings in the form of damping off or fungal diseases.

If you’re going to put forth the effort to start your seeds indoors, nurture them, and harden them off until it’s time to transplant, seed starting mix will give you greater success rates so you don’t waste seeds (or time).

What’s the difference between potting soil and seed starting mix?

Generally speaking, potting soil is a growing medium that contains topsoil (in other words, plain old dirt) and some combination of bark, perlite, vermiculite, peat, humus, manure, and/or other fertilizers.

Potting mix is a similar growing medium that’s usually soilless, though commercially, you may find the terms are interchangeable and refer to the same thing. (You should always check the label of any bag you buy.)

Potting soil and potting mix aren’t ideal for seed starting because:

  • They have a coarser texture than seed starting mix, and you’ll often find chunks of bark in potting soil.
  • They don’t drain as well as seed starting mix.
  • They’re sometimes too rich in nutrients.

It’s not the end of the world to use potting soil or potting mix to start your seeds, but you’ll be paying a premium for ingredients that aren’t needed for germination.

On the other hand, if you don’t want to mess with repotting seedlings and just want to plant the seeds in their permanent container, you can start your seeds in a good potting mix that’ll continue to help them grow sturdy and strong.

Get my recipe for homemade potting mix below.

The best DIY seed starting mix needs only 3 ingredients

That’s the benefit of making your own seed starting mix at home — no synthetic fertilizers or synthetic wetting agents to worry about, just simple organic ingredients to get your seeds off to a great start.

Together, these ingredients provide the perfect level of fluffiness, drainage, and moisture retention for starting seeds.

    Sphagnum peat moss (not to be confused with the coarser and more fibrous sphagnum moss that’s typically used to line floral baskets) is an excellent, sterile, moisture-retaining medium. The finer the fiber, the more water-holding capacity it has.

An alternative to peat moss is coco coir. This material is similar to peat in terms of look, feel, and moisture retention, but is made from the fiber of coconut shells.

Perlite is an ultra lightweight volcanic glass resembling white popcorn ceiling, and it provides drainage and aeration.

  • Vermiculite is a natural micaceous mineral, brownish and granular in appearance, with water-absorbing properties that facilitate re-wetting of the soilless mix.
  • All three ingredients are easy to find at most garden centers, but I’ve also linked my favorite sources online (below) if you can’t find them at your local nursery.

    Basic Seed Starting Mix Recipe

    • 1 part sphagnum peat moss (or coco coir)
    • 1 part perlite
    • 1 part vermiculite

    A “part” refers to any generic unit of measurement to make the quantity you need, as long as it’s consistent: a scoop, a bucket, or a bag of each ingredient.

    Combine all the ingredients in a clean tub or bucket, and saturate the mix with water. Stir the mixture with your hands or a trowel until it’s thoroughly moistened but not soggy (like a wrung-out sponge).

    Add as much water as the mixture will absorb. You might be surprised to see how much it holds — peat moss can absorb 16 to 26 times its weight in water.

    This initial watering makes it easier to keep the mix uniformly moist throughout the seed starting period, as peat moss can be difficult to re-wet if it’s been left to dry out.

    Fill your seedling pots with the homemade seed starting mix, add seeds, and sprinkle a thin layer of vermiculite over your seeds if they need darkness to germinate. (Your seed packets should give any special instructions.)

    You can save leftover seed starting mix for next season, or use it as the basis of your potting mix.

    How to make the best potting mix for transplanting seedlings

    With potting mix, we want to increase the ratio of peat moss (or coco coir) to up the moisture retention so our potted plants don’t dry out as quickly.

    A basic potting mix is a good starter medium for transplants, but you’ll want to amend it with compost, garden lime, worm castings, kelp meal, or other supplements depending on the nutritional needs of your plants.

    Basic Potting Mix Recipe

    • 6 parts sphagnum peat moss (or coco coir)
    • 1 part perlite
    • 1 part vermiculite

    Enriched Potting Mix Recipe

    • 4 parts sphagnum peat moss (or coco coir)
    • 2 parts compost
    • 1 part perlite
    • 1 part vermiculite

    Enriching your potting mix with compost will help your seedlings and transplants thrive after the cotyledons die off. I like to start with well-aged compost, then add other amendments that inject a jolt of nutrients as well as increase microbial activity in the potting mix.

    So just how cheap is this seed starting mix?

    Let’s do a little math here and see how much we can save with this DIY.

    A well-known brand of seed starting mix from a big-box garden center runs about $5 for an 8-quart bag.

    While that doesn’t sound like much, note that 8 quarts is only 0.27 cubic foot.

    Buying the individual ingredients from the same store means I can make a little over 1 cubic foot of DIY organic seed starting mix for around $8.

    The same amount of pre-made seed starting mix from the national brand costs $20. That’s more than double the cost for a product that’s ridiculously fast and easy to make.

    Some people might feel a little hesitant about the initial investment (2 cubic feet of vermiculite = $20, 2 cubic feet of perlite = $17, 3 cubic feet of peat moss = $12), but a little goes a long way.

    If you keep these ingredients dry, they’ll never go bad and you’ll have plenty for your seed starting and potting needs.

    Seed Starting Mix Sources

    Black Gold 8-Quart Canadian Sphagnum Peat Moss Plus | Premiere Horticulture 1-Cubic-Foot Sphagnum Peat Moss | Nature’s Premium 1-Pound Brick Coco Coir | GROW!T 1.5-Cubic-Feet Premium Loose Coco Coir | Black Gold 8-Quart Perlite | Espoma 1-Cubic-Foot Organic Perlite | Espoma 8-Quart Organic Vermiculite | Espoma 1-Cubic-Foot Organic Vermiculite | Dr. Earth 1 1/2-Cubic-Feet All-Purpose Compost

    This post updated from an article that originally appeared on March 15, 2011.

    Linda Ly

    I’m a plant lover, passionate road-tripper, and cookbook author whose expert advice and bestselling books have been featured in TIME, Outside, HGTV, and Food & Wine. The No-Waste Vegetable Cookbook is my latest book. Garden Betty is where I write about modern homesteading, farm-to-table cooking, and outdoor adventuring — all that encompass a life well-lived outdoors. After all, the secret to a good life is. Read more »

    The best DIY seed starting mix has only 3 ingredients. Save money and get my no-fail recipes for organic seed starting mix and potting mix you can make at home. ]]>