If you’re into composting, it’s likely because you want to do a little something for the environment or create black gold to help your plants grow.
Or probably both.
Compost wins in both these areas. Though the way it boosts plant health might surprise you!
It doesn’t work its magic on plants directly but rather through the soil in which the plants grow.
Let’s look at exactly how nature’s recycling process turns organic waste into new plant growth.
Does Compost Help Plants Grow Faster?
Compost helps plants grow faster by creating ideal conditions in soil with the proper characteristics they need to thrive.
This soil-enhancing supplement delivers almost everything on plants’ list of essentials.
Better airflow throughout the soil? Check. Enough moisture? Sorted. Nutrients? Covered. Plant-friendly insects and microorganisms? Yup, lots.
So, compost makes soil healthy. And healthy soil grows healthy plants.
The exact mechanisms taking place in soil that has been amended with compost are complex. Most people think that nutrients from fertilizers are what plants need. But we now understand that soil life is just as important. Compost works in different ways. But the life-enhancing properties provided by organic compost make this substance unique.
How Does Compost Help Plants Grow?
Compost is quite the multitasker. It enhances soil in various ways to create an environment that gets plants growing.
These are some of the ways compost creates a happy home for plants:
Compost Improves Airflow
Plants’ roots need oxygen. The humus content of decomposed organic compost changes the structure of poor soil. Compost encourages airflow around the roots so they can breathe.
Compost Keeps Moisture Levels Just Right
Compost creates a good water balance in different soil types, so roots are neither drowned nor dehydrated. Compost will hold on to water, making it available for plant roots. At the same time, drainage is improved, so that excess water drains away.
Compost Adds Nutrients
Compost gives plants a nutrient boost. The exact nutrients added to the soil depend on what went into the compost and its age. A more diverse range of compost ingredients will produce compost with a broader nutrient profile.
These nutrients are available to plants by a “slow-release” process. This is because the organic matter in compost is still slowly decomposing. The microorganisms responsible for decomposition change the substances in the organic waste, turning them into a soluble form that plants can use.
Introduces Helpful Insects And Microorganisms
Creepy-crawlies like earthworms and microorganisms like bacteria and fungi are soil-health superstars. For example, worms create spaces throughout the soil that let air and water flow.
The hardworking bacteria also break down organic matter into nutrients that keep plants vigorous. All these living things work together to feed plants what they need in what’s become known as “The soil food web.”
Effect Of Compost On Plant Growth
Compost doesn’t instantly supercharge plants. So, you won’t sprinkle compost over your plants and have them now grow like magic beans.
You’ll only get compost’s full benefits after adding it to your garden every year for a while. The soil will become easier to plant in and increasingly welcoming to plant life in time.
Although your plants will only experience max benefit from compost in the long-term, every application will make them grow stronger and healthier. Even the very first time you apply compost to your garden!
However, don’t try to speed up the process by giving your garden super-generous helpings of compost. It doesn’t work that way. Instead, you’ll stress your plants and stunt their growth by giving them too much compost.
This is especially true if your compost isn’t mature. Immature compost is still in the phase of curing. It uses up nitrogen to decompose things. This means there’ll be fewer nutrients for your plants.
For an idea of how much compost to feed your plants, let’s take your veggie patch: it needs just a 1-inch-deep layer over the area every year.
Be sure to only give your garden finished compost (dark brown, smells earthy, feels crumbly, and contains no bits and pieces you can recognize). Unfinished compost can hurt your plants, especially seedlings.
Do Plants Grow Better In Compost Or Fertilizer?
Top-quality soil rich in organic matter can be all that plants need to grow to their full potential. In the long term, topsoil enriched with compost is better than using only fertilizer.
It’s true… Fertilizer will make plants flourish. But the effects are only short-lived. The problem is that fertilizer destroys the delicate soil life that nature uses to keep plants healthy.
However, sometimes plants need extra nourishment. For example, if plants are struggling (one sign: they’re not flowering), their soil might be lacking certain nutrients they need. In this case, giving them a dose of fertilizer containing the specific nutrients they’re missing could get them growing.
Whereas compost feeds the soil to create an environment that gives plants the best chance to thrive, fertilizer provides plants with nutrients the earth might be lacking. Compost adds nutrients to the soil, but only in small amounts and slowly, so it won’t meet all plants’ nutritional needs.
Consider doing a soil test to check precisely which nutrients are lacking. Use a test kit like this for quick results. (Amazon)
You can get chemical or organic fertilizers. Chemical fertilizers work quicker but can be harmful to the environment.
Organic fertilizers work slower but tend to be safer.
Is Compost Alone Enough For Plants?
In some cases, you can plant in compost only. But planting in compost alone can give plants too much of some compounds and too little of others. The result? Not the lush greenery you had in mind. Instead, you could end up with weak, sickly, or even dead plants.
Topsoil is vital to thriving plant life. Compost shouldn’t replace the soil. Its job is to make it a more nurturing home for plants.