How To Prepare Soil For Planting Vegetables In Pots

Soil is life.

This is true for growing vegetables in pots.

So you want to have the best soil possible when starting seeds or transplanting into pots.

If you’re starting vegetable seeds, you want a good seed starting mix. And if you’re transplanting seedlings, you need a good potting mix.

Let’s look at what you need to consider when preparing soil for growing vegetables in pots.

1. Choose the right seed starting mix

If you’re starting seeds, some vegetables such as tomatoes, peppers, okra, and eggplant germinate well in a seed starting tray using a seed starting mix.

A suitable seed starting mix is necessary for successful germination and vigorous root growth in vegetable pots.

A high-quality seed starting mix should keep moisture while also allowing excess water to drain freely. This is important to prevent waterlogged roots, which can lead to suffocation and poor growth. Proper aeration is essential for root health as it allows the roots to access oxygen, which is necessary for their metabolic processes.

Coconut coir is a popular seed starting mix because of its ability to hold moisture, aerate, and promote root growth.. Coconut coir is derived from the husks of coconuts and is known for its excellent water retention capabilities. It also has a fibrous texture that allows for proper drainage and aeration.

My choice is to use a mix made with coco coir and compost so the seeds get the right texture for germination and nutrients as they develop into seedlings.

Once the seeds have germinated into seedlings and grown 2-4 inches, you can transplant them to the bigger pot with good potting mix. The plants can be gradually hardened to the outdoor conditions before the pot is moved to the outdoor garden for further growth.

2. Choose the right potting mix to grow vegetables

Container plants need a lighter potting mix for optimal drainage and aeration. The ideal potting mix for vegetables should contain materials such as perlite, vermiculite, peat moss, or coco coir.

These components contribute to the mix’s ability to retain moisture while also allowing excess water to drain away. This is crucial in preventing waterlogged roots, which can lead to root rot and hinder the plants’ growth.

Besides drainage, a good potting mix should also provide the nutrients for the vegetables to thrive. Some potting mixes include organic fertilizers or compost for plant health..

Ready-made potting mixes are readily available commercially, offering convenience for gardeners. You can create a custom potting mix with peat moss, coco coir, perlite, vermiculite, compost, and organic matter.. This allows gardeners to tailor the mix to meet the specific needs of their vegetable plants.

I use ready-made potting mix myself that is made using a combination of garden soil, compost, and coco peat. It works really well for my plants, such as peppers, tomatoes, spinach, and cilantro.

3. Make your own seed starting mix

There are many ways to create seed starting mix from simple to complex depending on how much you want to work on it.

My simplest idea is to use coconut coir and compost. Mix 2 parts coconut coir with 1 part compost and that should be sufficient to use as a seed starting mix. Make sure to mix them well.

After creating your seed starting mix, it is important to store it in a lidded container in a cool, dry place. This will help prevent any moisture or nutrient loss. Before planting your seeds, ensure the mixture is evenly moist by thoroughly wetting it.

How much seed starting mix will you need?

This will depend on how many seeds you intend to germinate and how many seed starting trays you’ll be using.

Roughly, each seed starting tray depending on the size could hold 1-2 cubic inches of potting mix. So if you have 10 seed starting trays, you’ll need around 20 cubic inches of seed starting mix.

I just get the seed starting mix in bulk as it helps me save money than if I would have got small quantities of it. Especially helps save on the shipping and reduce the overall amount I spend.

4. Make your own potting mix

You can customize the ingredients in your own potting mix. To make a high-quality potting mix, gather the key components: organic matter, soil amendments, and nutrients.

Organic matter can be obtained from compost, which is rich in nutrients and beneficial microorganisms. Soil amendments like perlite and vermiculite help improve aeration and drainage, while coco coir, a sustainable alternative to peat moss, aids in moisture retention.

Here’s my simple way of making your own potting mix. Combine 1 part coco coir, 1 part sterilized garden soil, and 2 parts compost.

Another option is to combine 1 part coco coir, 2 parts compost, 1 part vermiculite, 1 part sterilized garden soil, and 1 part perlite.

Thoroughly mix these components to ensure even distribution, either by hand or using a large container and shovel. Once mixed, your potting mix is ready for use.

If making your own potting mix is not your preference, there are many commercial options available for purchase. Look for high-quality potting mixes specifically designed for growing vegetables in pots. These ready-made mixes often contain a balanced blend of organic matter, soil amendments, and nutrients.

How much potting mix will you need?

The main thing would be to know the pot size in which the plants will grow. You’ll need pots of different sizes depending on the type of vegetable you want to grow in them.

Fruiting plants need large pots that are at least 12 inches, while leafy vegetables and herbs can do well in 8 to 10 inch pots. Root vegetables will need pots of varying sizes depending on how large the roots will grow.

Here’s a table that shows the approximate volume that the different sizes of pots can hold.

Pot size	Gallons	Cubic Feet	Diameter (inches)	Height (inches)
1 Gallon	1.3	0.18	8	6
2 Gallon	1.5	0.2	8	7
3 Gallon	3.9	0.52	11.8	8
5 Gallon	6.8	0.91	14	10
7 Gallon	8	1.1	14	12
10 Gallon	13.4	1.8	18	13

Next, count the number of pots you will be using. Considering the number of different vegetables you plan to grow, calculate the quantity of soil accordingly.

So, for example, if you have 5 pots that are 8-inches in size, you’ll need about 5 * 1.5 = 7.5-10 gallons of potting mix.

Similar to the seed starting mix, I get the potting mix in bulk so I can save on shipping and get it at a cheaper cost. I can store the unused potting mix for later use with other plants that I grow.

Read more:

• What Size Container Is Suitable To Grow Vegetables?

5. Reuse potting mix from the last growing season

Reusing potting mix from the previous growing season offers a sustainable and cost-effective solution for gardeners, promoting environmental sustainability and reducing waste. However, before reusing the potting mix, it is crucial to properly clean and prepare it to ensure the health and viability of the plants.

To begin the preparation process, it is essential to remove any plant debris from the used potting mix. This includes dead leaves, roots, and stems. By using a garden fork or hands, gently loosen the mix and eliminate any larger debris.

Tip: If you’re reusing the pot, I would recommend rinsing it with a solution containing 1 part bleach and 10 parts water. This helps remove any pests and diseases that may be in the pot from the last planting.

Besides removing debris, replenishing the nutrients in the potting mix is important. Over time, the nutrients in the soil can become depleted, which can negatively affect the health and growth of the plants. To address this, organic matter such as compost or well-rotted manure should be added to the mix. This will not only replenish the nutrients, but also enhance the overall structure and fertility of the soil.

Consider incorporating organic fertilizers into the potting mix. These fertilizers release essential nutrients slowly, providing a sustained source of nutrition for the plants throughout the growing season. Look for fertilizers specifically formulated for container gardening and vegetable plants.

Thoroughly mix the organic matter and fertilizers into the potting mix, ensuring even distribution of nutrients. Once prepared, the reused potting mix is ready to be used for planting vegetables in pots.

Read more:

• Do You Throw Away Old Potting Soil?

6. Add the right nutrients to the potting mix

Adding the right nutrients to the potting mix is essential for promoting optimal plant growth and development in container gardening. While the potting mix may not provide all the necessary nutrients, organic fertilizers can be used to supplement the soil.

It is important to choose fertilizers that are specifically formulated for vegetable plants and container gardening, as they provide a balanced mix of essential nutrients. These nutrients, such as nitrogen, phosphorus, and potassium, are crucial for healthy plant development and overall growth.

Compost is another valuable resource for enriching the potting mix with nutrients. Besides adding organic matter, compost improves the soil’s structure and fertility. It is advisable to incorporate well-rotted compost into the mix, ensuring that it is evenly distributed.

My favorite addition to my potting soil is compost and organic matter such as neem cake powder and mature cow mature to give a boost of organic matter and nutrients.

Read more:

• Add Compost To Container Plants: 7 Expert Tips
• Does Potting Soil Contain Fertilizer?

7. Get the best seed starting mix for growing vegetables

If you don’t want to bother making your own seed starting mix, you can get a lot of pre-made ones on the market.

Commercial seed starting mixes offer convenience and are often formulated with a combination of organic matter and nutrients, providing an ideal environment for seed germination and early plant growth. These mixes are typically sterilized to prevent weed seeds and diseases, although they can be more expensive.

Here are some good ones that you can find on Amazon.

• Mosser Lee SucSeed Premium Seed Starter
• Hoffman Seed Starter Soil
• WONDER SOIL Organic Seed Starter Pellets

8. Get the best potting mix for growing vegetables

You can do the same with the potting mix if you don’t have the time or inclination to make your own. You can get pretty good potting mix in stores or online though you have to spend a little money on them.

You want a potting mix that has good organic matter along with the materials that ensure good drainage and aeration. You can get either sterile potting mix or those that contain nutrients as well.

Commercially available potting mixes specifically designed for growing vegetables in containers offer convenience and reliability. These mixes are formulated to meet the specific needs of vegetable plants, ensuring optimal root development and abundant yields. It is advisable to look for mixes labeled as suitable for vegetable gardens or those recommended for the specific type of vegetable you are planning to grow.

Here are some good potting mix options you can find on Amazon.

• Espoma Organic Potting Soil Mix
• Back to the Roots All-Purpose Potting Mix
• Burpee Organic Potting Mix