Seed Starting Mixes

Seed Starting Mixes

Gardeners know the secret to getting seeds to turn into healthy and growing plants is to use a seed starting mix. Seed starting mixes create an ideal environment for seeds to sprout and turn into a thriving plant. They are lighter and finer than the soil, which can help ensure that a plant's fragile and short roots are able to grow properly to get the plant off to a healthy start.

If you're looking for the best seed starting mix, you've come to the right place. We've reviewed some of the top options on the market to help you narrow down your choices and select the best product to meet your gardening needs.

Top 4: Best Seed Starting Mixes

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Black Gold 16-Quart Seedling Mix

We selected the Black Gold Seedling Mix as our top pick is formulated with sphagnum peat moss along with other ingredients, such as perlite, dolomite lime, and an organic wetting agent, to help seeds sprout and grow.

The mix of ingredients helps to ensure seeds and young plants get sufficient moisture and air flow to sprout and grow. The manufacturer also specifically formulated this seed starting mix to help the roots of a newly germinated seedling grow.

Additionally, this mix has been listed by the organic material review institute as a satisfactory option for growing organic foods or fiber. The mix comes in a generously-sized 16-quart bag.


  • The sphagnum peat moss helps retain moisture for plant growth.
  • This mix is formulated to help grow strong roots.
  • It has been listed by the organic material review institute.


  • Some customers said the consistency isn't ideal and that mix can dry out too fast.

See our review on: Worm Composters

Espoma 16-Quart Organic Seed Starter Premium Potting Mix

The Espoma Organic Seed Starter Premium Potting Mix is another excellent choice. This is a good organic option for those looking to grow organic fruits and vegetables. It is suitable for use with all types of seedlings and cuttings, making it a very versatile option.

The mix Is designed to retain moisture to allow seeds to sprout and deliver sufficient water to help young plants grow and thrive. It also is formulae to promote root growth to get plants strong enough to transport to a flower pot or garden.

The manufacturer recommends using this product to start seeds indoors in the early spring or late winter to get seeds started to transfer to a garden when the temperature warms up. You should use it in a shallow container that has drainage holes and place the seeds in a bright area (that isn't in direct sunlight). The manufacturer recommends misting the seed starting mix to keep it moist and to transplant plants to a larger flower pot or an outside garden once the true leaves appear.

This starting mix is mostly sphagnum peat moss, but also includes other ingredients such as perlite, humus, lime, and earthworm casting to help seeds grow. A special ingredient, My-tone, is also added to the mix. This is a blend of mycorrhizae, a fungus, that can help retain moisture and allow for healthy root growth.


  • This is an organic option.
  • It is formulated with sphagnum peat moss to get seeds off to a good start.
  • The My-tone added to the mix also helps to retain moisture and help roots grow.


  • This mix may be drier than some other options.

See our review on: Best Rooting Hormones

100 Jiffy 7 Peat Pellets

Next, take a look at the seed starting pellet from Jiffy. Each pack include 100 easy-to-use pellets. Simply place a pellet in a little water, and it will expand to create an ideal environment for a seed to sprout and grow.

No soil is needed to use these pellets. Once the seed has sprouted and the roots have developed, the plants will be ready to move to a larger pot or an outdoor garden. The pellets are formulated to minimize the shock to a plant and prevent root damage when they are ready to transplant.

Each pellet is just over 1.5 inches wide, the perfect size to put in seeding cups. Their small size also makes them easier to use than larger boxes of potting mix, since you'll only need to take out and carry what you need, rather than dealing with a large bag. Once water is added, each pellet expands to about seven times the original size to offer the perfect place for planting seeds. Keep the remaining pellets in the sealed plastic bag so they're ready when you need them.

To make sure seeds and new plants get sufficient water, the pellets are designed with a fine netting. This netting also helps to protect the fragile roots of a new plant when transplanting it.


  • These are lighter and easier to deal with than a large bag of seed starting mix.
  • The pellets expand to seven times their original size when water is added.
  • The mix is designed to ensure seeds and new plants get sufficient moisture and aeration.


  • The size of the pellets in each bag may vary from what is advertised online.

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Hoffman Seed Starter Potting and Planting Mix, 10 Quarts

The Hoffman Seed Starter Potting and Planting Mix is a soilless seed starter that is designed to ensure seeds get off to the best start possible. It is also suitable to use for root cuttings and transplanting.

A mix of six different ingredients, including Canadian sphagnum peat moss, horticulture vermiculite, limestone (pH adjustor), and a wetting agent. These ingredients make this a lightweight mix that offers the perfect spot for new seeds to germinate. It offers sufficient air flow and moisture retention to give seeds and new plants what they need to thrive.

The pH of this soil can range from 5.6 to 5.9, which is ideal for plant growth. This mix comes in a 10-quart zippered bag.


  • The Canadian sphagnum peat moss and other ingredients provide moisture and airflow to seeds and plants.
  • The pH is between 5.6 and 5.9.
  • You can also use this seed starting mix for transplanting and root cuttings.


  • This is only a 10-quart bag, whereas many other mixes come in a 16-quart bag for a similar price.

See our review on: Soil Moisture Meters

Buying Guide

There are different things to consider before you purchase a seed starting mix. Read through the buying guide below to help you determine which features are most important to you when shopping for the best seed starting mix.

Type and Ingredients

The most important thing to consider when choosing a seed starting mix is the ingredient list and the properties of the mix. First, look for a lightweight mix that drains well. This will better allow a sprouting seed and tiny roots to get off to a good start.

You should also look for a mix that allows for plenty of air circulation and absorbs water well. This help makes sure the roots of a seed will be able to make it out of the shell and then will have sufficient space to grow.

Some ingredients you should look for include:

  • Sphagnum peat moss: This is present in most seed starting mixes. It is very absorbent to ensure there is sufficient moisture for budding seeds.
  • Perlite: Perlite is tiny pieces of a volcanic mineral. It helps soil drain quickly and provides a cover for seeds to make sure they have enough moisture.
  • Vermiculite: Vermiculite is another ingredient that can help ensure the mix stays moist enough for your plants to grow. Because of this property, it can also reduce the frequency with which you'll need to water.
  • Coconut coir fiber: You may see this ingredient in some seed starting mixes in the place of sphagnum peat moss. It is able to hold 8 times its weight in water, which means it will keep seeds and young plants moist.
  • Diatomaceous Earth: Also referred to as DE, Diatomaceous Earth is a natural fertilizer that keeps insects away from your seeds and plants. It is made up of very small fossilized plants called diatoms, which are similar to algae. Numerous helpful minerals are also found in DE. These include silicon, magnesium, sodium, iron and calcium. Because of its composition, DE is also able prevent toxins or bacteria from attacking plants or seeds.

pH Level

Next, pay attention to the pH level of each seed starting mix you're considering. A pH level between 5.5 and 6.5, which is slightly acidic, is best for plat growth in most areas. Areas that have more rainfall will do best with seed starting mix with a pH between 5.6 and 5.9.

Size and Quantity

Bags of seed start mix come in a variety of sizes. Look for one that offers enough for your projects without being so large that you'll be left with a lot of extra mix that will go to waste.


Finally, consider the manufacturer's reputation for each product you're considering. When possible, select seed starting mixes from well-trusted manufacturers. Also, look through some user reviews to confirm that individuals who have tried the product are satisfied with the results it delivered.

Our Favourite

If you're looking for the best seed starting mix, we suggest trying the Black Gold Seedling Mix. This mix includes sphagnum peat moss, an organic wetting agent, dolomite lime, and perlite to help seeds sprout and grow healthy and strong roots. The formula is designed to be an ideal choice for root growth. It also helps to ensure seedlings receive the moisture and airflow they need to thrive.

Black Gold 16-Quart Seedling Mix

It comes in a 16-quart bag to help you get a large number of seeds off to a great start and ready to be transplanted to a larger flower pot or a garden.

While we think the Black Gold Seedling Mix is a great pick, all of the other seed starting mixes on our list are also great products. If one of them looks to be a better match for your needs, don't hesitate to pick it up instead!

Frequently Asked Questions

What is seed starting mix?

A seed starting mix is designed to help get started growing into plants. Seed starting mix is lighter and finer than soil, which can help the very short and fragile roots of a budding seed to grow. Seed starting mixes help seeds grow into plants and allow those plants to become strong enough to transfer into soil.

What is the difference between potting mix and seed starting mix?

Both potting mix and seed starting mix are regularly used in gardening. Potting mix is best for re-potting plants and providing them with a nutrient rich soil to help them grow. Potting mix isn't as good for starting seeds, however. Compared to seed starting mix, potting soil is too rich for new seeds and young plants. It also doesn't drain as well as seed starting mix. For a seed to start growing, drainage is important to make sure the tiny seeds and roots don't get too flooded.

Seed starting mix is the best choice for starting seeds for a few reasons. First, it is lighter weight than potting soil. This allows tiny roots to grow better. Seeding starting mix also offers a better germination process than potting mix. Finally, seed starting mix offers more air circulation and absorbs water more easily. This will help the seed to sprout and grow into a healthy plant.

How can plants grow in a soilless seed starting mix?

It may seem counterintuitive that seed starting mixes don't contain soil. We all grew up learning that soil was one of the necessary things all plants need to grow. While this isn't untrue, very early in a plant's life, they're able to gain all the nutrients they need from their seed. Once they've grown a bit, then they will need to be transferred to soil to continue getting what they need to keep growing.

Should you get sterilized seed mix?

Sterilized seed mix has been heated to high enough temperatures that most pathogens and bacteria won't be able to survive. While your plants may be able to grow in a non-sterilized mix, it will be more likely that mold or fungi will be present. These could kill a more fragile seed or young plant. So, looking for a sterilized seed starting mix is probably the best idea.

Should I use a seed starting mix?

The answer to this question will vary. Some garden soils are conducive to growing new seeds, and you may find that you don't need a seed starting mix. However, other areas are too humid and are more likely to have mold or fungi present. Since mold and fungi can kill weak seeds, you would do best in these situations to choose a seed starting mix to get your plants growing.

Can you start flower seeds in egg cartons?

Yes, egg cartons can work as a seed starting tray. Some egg cartons are biodegradable, and you'll be able to cut the carton to plant it in the soil when your plants are ready. Others are not biodegradable, so you'll need to transfer the started plant to the soil when it is ready for more space to grow.

Can you start seeds in eggshells?

Yes, you can use eggshells to start seeds. Eggshells can create the perfect spot for a new seed to sprout, and once the tiny plant is ready to be transplanted, you can simply plant the entire eggshell, and it will compost in the dirt.

How many seeds should I plant per hole?

Every seed you plant likely won't grow, so it is generally recommended to put between two and three seeds in each hole. This will help ensure enough seeds sprout to provide the desired number of plants.

Should you soak seeds before planting?

Soaking seeds before planting isn't required, but many individuals find that doing so offers better results. Soaking a seed with a hard shell can help loosen the shell to make it easier for the seed to sprout when placed in soil. Soaking seeds can also increase the moisture rate and soften the seed. These will also make it easier for the seed to grow when placed in soil or seed starting mix.

However, not every type of seed should be soaked. Avoid soaking seeds that are very small and challenging to handle such as spinach, carrots, celery, turnips, lettuce, or radish seeds.