Will Plants Grow In Compost Only? ( the Power of Compost )


Have you considered growing the plants without soil, just in compost?

The practical gardener would find it far simpler to plant some seeds in a container filled with handmade compost from their backyard, water the soil, and watch the plant develop. Although it’s a good concept, does it truly work?

There are just too many advantages of compost materials for the soil and plants for any farmer to ignore.

Because it is a direct source of several essential nutrients, it also goes by the name “black gold.” Many farmers are unsure if they may plant directly into compost mixed because of how much it resembles soil.

Because of the circumstances involved, there isn’t a clear response whether the plant can grow in the compost only or not. The amount of soil depends on the sort of plant you’re cultivating.

Typically, Plants will require some dirt unless you’re growing little veggies, like onions, that don’t need much structural support.

Problems When Planting In Compost Without Soil

Different composts disintegrate at various speeds. Temperature, humidity, and the materials that are added to a compost pile, all have an impact on the pace of decomposition.

Materials shrink throughout the composting process until they are the size of crumbs, and then the crumbs finally cluster together. When compost is ready for use, it can be as little as one-third the size of a pile that has been left unattended for up to a year.

  • Compost quickly drains. In fact, one of the purposes for the addition of compost to the soil is to enhance drainage. Your plants would get incessantly thirsty if you put them in only compost. Water will quickly drain through compost as you add it. No matter what kind of compost you have, it will always drain quickly.
  • Without soil, compost won’t have the stability that many plant species need for their roots to anchor. When planting without soil, it is more likely that the plant’s root ball won’t have the support in a structure that is needed to keep the roots in place. Therefore, even if you are successful in growing your plant, you will probably notice that it leans to one side or that the stem completely collapses since it lacks the structural support to keep it upright.
Advantages Of Compost And Soil MixDisadvantages Of Compost
Compost improves overall soil structure.Compost dries out fast.
Compost and soil mix provides the correct amount of moisture.If buying in the store, compost can be expensive.
The soil mix is well draining.Not providing stable support.
Provides the exact amount of needed nutrients.Compacts quickly.
The need for fertilizers is reduced.Sometimes leads to excess nutrients

Plant’s Nutritional Needs

compost soil used in gardening
Photo by Sasha Kim on Pexels.com

Compost is used to aid in the soil’s nutrient absorption by plants. Based on nutrient load, soil quality is determined.

Most soils of high grade are mineral-rich. Because over half of soil’s nutrition comes from minerals that aren’t balanced in most composts, the soil is the primary source of nourishment for plants.

Soil can contain minerals in amounts ranging from 45 to 49 percent. Which is received from water, air, and soil. 

Mainly, the needed minerals include calcium, iron, sulfur, and magnesium. The organic content of regular dirt ranges from 1 to 5 percent. These primarily come from plants that are decaying, including food and animal products.

This 5% organic matter contributes to soil fertility, which supports plant growth. Most compost won’t contain as many nutrients as is required to support good plant development without organic matter. Half of the ingredients that a plant requires are organic and minerals.

The compost is crumbly, so water will drain quickly. Therefore, the more compost you use, the more watering has to be frequent. For tall blooming plants, a solid thick and strong soil foundation may be necessary to support the plant’s weight.

Will All Plants Grow In Compost Only?

When using only compost and nothing else, it may allow you to grow lighter plants effectively, so keep an eye on the pH level of the soil and don’t set your expectations up.

However, most plants need organic matter which can only be found in high-quality soil which also need to be replaced regularly. Compost may assist plants in absorbing nutrients.

Compost typically can be only used for soil improvement. It is an amendment that is typically ineffective on its own but works to increase the fertility and quality of the soil.

Only on little, light plants have some individuals found success with planting in compost alone.

It can be challenging for plants to flourish in such an environment because of their dependency on the minerals and rock fragments in the soil.

But once more, it is pretty tempting to put some plants in a pot and cover it with compost. After all, all the nutrients needed for development are available right away.

Even if a plant is grown using just compost and grows to maturity, there will still be obvious inadequacies. Because the compost mixture consists primarily of decomposed organic waste, it drains quickly. For instance, when you leave a section of compost without soil support, it dries up.

Even though generally the compost is not recommended to only be used for the plants. Some specific greeneries actually do fine in just compost, without any additions. So, let’s discuss them.

What Plants Can Be Grown In Compost Only?

Some plants are capable of growing right in compost. Those are the ones that don’t need structural support. It means that the weight will not affect the roots to move around and they won’t fall over. 

Vegetables, small tomatoes, baby carrots, Cucumbers, Zucchini,  and spring onions are a few among those that can flourish in the compost.

However, even those vegetables need a special environment and care. You will have to check the pH level. It’s an ideal setting for vegetables if the pH level is between 6.0 and 7.0. You may also look inside the pile to see what’s within. Its uniform composition demonstrates readiness for usage.

Start Seeds In Compost

If you have plants, probably a little vegetable garden, It must have occurred to you that you might start seedlings in the compost.

Why not? Since this substance resembles garden soil, it may also provide your plants with unrestricted access to nutrients.

You may consider sowing seeds in compost because you want what is best for your plants. However, the question is, is it possible to start seeds in the compost? And will they grow?

The appropriate circumstances are necessary for the seeds to sprout, though. For instance, before being viable for plants, compost material needs to be thoroughly degraded into its humus condition. In any other case, the seedlings might be killed by the compost mixture’s strength at this point.

Bottom Line

Pure compost can be unstable and have issues with water retention when used to grow plants. Compost, when combined with topsoil, is a water-saving miracle because it promotes effective drainage through dense soil.

However, when used alone, compost soon drains and dries up.

Because it is lighter than typical soil, it cannot provide robust root systems the solidity they require.

Additionally, over time, it compacts, which is problematic for pots because they will look empty after a week or so. Despite the fact that it may be enticing, pure compost is not actually a good idea. Not that you should never plant in compost, though.

Your plants just require an inch or two of excellent compost mixed with your current soils.

Applying a layer of compost to your garden soil mixture is one of the best uses for it. Then, you may fulfill your ambition to give your plants enough nutrients while also benefiting the soil and the plants.

Peride Beradze
Peride is an avid planter, Tour Manager and freelance writer. She is a plant collector who mainly focuses on succulents. She loves studying cultures, traveling and learning new languages.

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