Preparing Garden Soil for Growing Hostas

Last Updated on August 15, 2022 by Stephanie

Hostas thrive in moist, nutrient-rich, retention, porous soils that have pH 6-7 like loam soil or soil which has been amended with lots of organic matter.

The sandy or heavy clay soils require amendment with substances like compost leaf mould, manure or leaf mould to an extent of 16 inches prior to planting hostas.

Optimal soil for hostas quick guide:

Continue reading to find out how to amend your garden soil to grow hostas and the reasons you should mulch around hostas each year at the beginning of spring for healthful hosts…

Hosta Soil Requirements:

A well-drained soil is an essential characteristic of hostas since they are not able to be able to tolerate soil that is overly saturated for prolonged periods of time. The soil that is boggy can cause disease root that causes rot that can cause death to the hosta.

The roots of the hosta are quite in depth for plants of this size, so the soil must be able to drain well to an average depth of 16 inches since it will allow for the dimensions of root balls after the more robust hosta varieties have been established.

It is equally crucial that the soil is able to hold water as hostas are extremely thirsty plants due to their huge leaves that release a lot of water vapour, so an ongoing source of moisture is essential.

The soil must be able to allow the excess moisture to flow away from the roots of the hosta while keeping moisture in the soil and allowing the roots to draw on the soils moisture whenever they require.

Soil Fertility. Hostas require soil that is rich in nutrients for their growth to be at its best. Hostas are a foliage plant with many beautiful leaflets which require lots of Nitrogen to flourish each year.

Hostas do not thrive in soils that are sandy or clay because these types of soils do not just drain fast but they also do not keep nutrients.

The clay soils are regarded as ideal because the clay content is extremely effective in keeping in water-soluble nutrients like Nitrogen as well as Potassium.

Organic soils are ideal for the growth of hostas, especially with the mulching in the spring, to provide more nutrients.

The most massive hostas like Patriot and Sum and Substance that develop to a massive length that is 36 inches (90 centimeters) require fertilizer addition in the spring to expand to their maximum size and to produce the desirable foliage , as they have more demands on nutrients than smaller-sized hostas.

Soil Structure. The ideal soil for Hostas is a lightweight flexible material that has an areated shape. Hostas roots are fleshy, white and extend very deep in the soil compared in size to what the plant is.


The roots that are deep are a result of the plants dependence on a steady nutrition and moisture. The compacted soil hinders the growth of roots, which can result in an insufficiently established root system. It will also increase the likelihood of stunted growth in the leaves as well as the vulnerability to drought.

So, planting directly into clay soils that are heavy is not recommended and the soil may need significant amendment or amending. You can also plant the hostas in pots instead.

Sandy soils offer the aerated structure that hosts like, but they are usually lacking in nutrients and drains too fast. They also require large amounts of organic matter added to the soil prior to planting.

(Read for more information about the process of amending sandy soils to plant hostas)

pH of the soil. Hostas like a pH between 6.5 up to 7.5 which is slightly acidic, neutral or alkaline. This is the soil pH of the majority of garden soils due to the fact that the vast majority of organic matter can be described as moderately acidic or pH neutral after it has been completely decomposed, so the majority of gardeners dont have anything to be concerned about.

But the chalky soils are usually too acidic and rapid draining for hostas that are growing. In soils that are alkaline, the hosta is unable to absorb all the nutrients they require and will develop poorly or even die.

In gardens that have chalky or limey soils , it is much easier to cultivate hosts in containers.

Composition. Loam is the best soil kind for many plants in the garden because it is able to hold nutrients, keep moisture, and allows for a good drainage.

If you happen that you have soil with loam, then you can plant hostas with no needing to alter or amend your soil.

Hostas can thrive in virtually any garden, provided they have an abundant organic matter within the soil. The soil can be made more suitable to grow hostas as well as other plants that are popular like roses and azaleas, by altering the soil using organic matter.

Add Mulch Every Spring

The addition of mulch around your hostas will ensure the soil is continually improving in structure and provides optimal conditions for the growth of hostas. It is recommended to mulch your the hostas each year because:

  • Mulch helps conserve water by reducing the rate of soil evaporation and helps ensure that the surrounding soil hostas roots damp despite the higher temperatures of summer.
  • Organic matter can add fertilizers to soil, and also feed the soils ecosystem, ensuring the hosta has access to the nutrients it needs.
  • Mulch improves the surface of the soil, allowing water to penetrate the soil to get to the root. Soils that are not mulched can become hard during summer, which can cause surface run-off and redirects water away from the hostas roots.
  • The roots are cooler during the summer months and are more protected during winter, which improves the hostas resistance to freezing winter temperatures.
  • The mulching option could mean the difference between needing to water your hosta daily during hot weather or even every couple of days, which can save a lot of effort.

Spread a 1 inch layer of mulch around the hosta at the beginning of spring when the temperature is rising. Make sure there is an opening between the mulch layer and crown because the hosta leaves above ground doesnt want to come into contact with moist materials for long periods of time.

The best mulching materials are the same as soil amendments needed to plant the hosta and leaf mould, with compost, and manure being excellent alternatives as they are extremely effective and conserve water when in comparison to other kinds of mulch.

Amending Soil for Growing Hostas

A proper preparation of your soil prior to planting hostas will ensure that the plant is healthy, develops to its fullest potential, as well as being resistant to snails and other diseases.

Three soil amendments that make sure that the soil has the necessary characteristics to grow Hostas include:

  1. Leaf mold
  2. Garden compost
  3. Manure that has been well rotted

Each of the three materials has the capacity to hold water so that the roots of the hosta can draw on the moisture whenever it is needed. This improves the plants resistance to drought.

The manure that is well rotted particularly provides a great dose in Nitrogen that is an essential nutrient that is needed by the hostas in most quantity in spring to encourage growth of the foliage.

It is essential to ensure that the compost and manure is properly rotten as recently deposited manure could burn the root in the plant.

The three components provide the ideal porous structure that permits the drainage of water and allows air to the roots to allow breathing and for the formation of the roots.

If there are all three of these ingredients Mix 1/3 each of the ingredients in preparation to plant the hostas in the soil in order to get the properties and wide range of nutrients from the three ingredients.

Other substances that are effective include pine needles, decayed wood bark because they improve the structure, but they dont provide the same amount of nutrients as compost, leaf mould and manure, so they should be used in smaller amounts.

It is recommended to amend the soil to 16 inches for the bigger hosta varieties in order to allow for their root systems to grow and around 12 inches for smaller varieties.

If you alter too little the area of garden soil the roots might not integrate into the soil because of the stark contrast of the nutrient-rich, moisture retained soil, the amended soil, and the less suited surrounding soil.

In the event that your garden is too dry, or too compacted, or is a clay-rich soil The solution is similar. Include a lot of organic matter to your garden boarder prior to planting.

Compost improves sandy soils by retaining moisture , boosting nutrients and reduces compaction as well as improving drainage for clay soils.

Beware of this Mistake!

Avoid using wood bark or other materials that have not been completely decomposed in a mulch or soil amendment. Decomposition of these materials could result in an temporary nitrogen deficiency in the soil.

Decomposition process for organic material needs Nitrogen that is derived from the soil surrounding it. This means that there is lower levels of Nitrogen present in soil around your Hosta which could hinder the growth of the plant . In addition, it may be necessary to fertilize it in the spring to make up for the deficiency.

Other nutrients, including nitrogen, are added to the soil when organic matter is fully decayed, so wait about a year for the materials to decompose before altering the soil to plant or spreading it as a mulch.

Key Takeaways:

  • Hostas requires soils that hold moisture , but have a porous structure, so that water is able to drain away from the roots to ensure that the soil doesnt get boggy.
  • Hostas require soil that is rich in nutrients. Hostas with larger sizes require fertilizer in the spring to allow them to grow fully.
  • Add leaf mould, compost or manure that is well-rotted prior to planting. Plant to a depth of approximately 16 inches to allow for the roots of an established hosta.
  • The sandy soil drains too fast for hostas, and clay heavy soils drain too slow. Make sure to amend both with lots of organic matter prior to planting to enhance the soils structure or grow hostas inside pots instead.
  • Apply mulch to the spring to help conserve water and also add fertilizers to your soil.


Went from an inexperienced gardener to a half-decent one over 10+ years. I cover anything from general indoor plant guides and lawn care, to succulents and flowers. Super happy to share my tips and tricks with you :)