Whether you’re growing flowers, vegetables, shrubs or even trees, the vitality of any garden starts with choosing the right type of soil and soil nutrients. Read on to learn more about the different types of soil and potting mixes to ensure your garden thrives.
How Soil Helps Plants GrowAs the foundation for any plant your soil provides four essential elements to ensure healthy, sustained growth.
Provides Moisture and NutrientsDid you know that soil is what helps facilitate a plant’s water supply? It also helps provide the plant with the nutrients it needs to grow.
Anchors the RootsSoil is what holds everything together. It helps anchor the roots to keep the plant stabilized.
Helps Plants BreatheThe spaces between soil particles contain air, which is absorbed by the roots to help breakdown sugars and release energy, so the plant can thrive.
Provides InsulationSoil also protects the plant’s roots from temperature fluctuations during hot or cold periods.
The Different Types of SoilUnderstanding the different types of soil is the first step to creating and maintaining your dream garden.
Garden soil is essentially enriched topsoil, usually incorporating a variety of soils and textures, and often mixed to target particular types of plants (flowers, vegetables or herbs). Garden soil can be mixed with your native soil to help deliver the pH levels and nutrient content your plants need to thrive. It can also assist with aeration, helping to avoid soil compaction and maintain proper moisture retention. Use garden soil only for in-ground gardens however, not containers or raised beds.
Unlike garden soil, topsoil is less a growing medium and more of a general purpose landscape material. It’s not enriched, but it does contain valuable organic matter from leaves, grass, tree bark etc. This makes it an ideal lawn additive for reducing thatch and increasing pest and weed resistance. Topsoil can also be used to fill the lower layer of raised bed planters, and to level off low spots in your lawn prior to laying sod.
Organic soil is a blend comprised of plant-based organic matter. This type of soil contains carbon-based material that is or was once living. Organic soil has been naturally amended by the decomposition of plants and living organisms.
Potting mix is specifically made for use in flowerpots and containers. The ingredients are designed to offer the right amount of drainage and airflow while also decreasing soil compaction. Potted plants only have so much space for roots to stretch out, so potting mix helps ensure flowers and plants have the nutrients they need. It should be replaced every year.
Made from raw wood products like bark, mulch is a top dressing soil used to help control water retention and soil temperature. It also helps prevent weeds from growing. Mulch is best used for large gardens and landscape plants to help them stay moist longer, requiring less watering.
What Types of Soil Do Your Plants Need?Not only do different types of gardens have different soil needs, so do the different types of plants. Here’s what you need to consider and look for to make sure you have the right type of soil for your plants.
- Choose soil with organic materials like peat moss for added drainage
- Use compost to add nutrients
- Lightweight soil helps flower roots to grow and spread, and also helps to anchor the flower
- Every flower is different! Be sure to research each type of flower you’re planting to ensure you have the soil that meets their needs
Fruits and Vegetables
- Soils designed to manage moisture will help protect against over or under watering
- Adding compost and organic materials to soil helps give edible plants the nutrients they need
- Double check the watering requirements for specific fruits and vegetables – they often have higher requirements than other flowers and plants
Grass and Lawns
- Soils with composted materials, fertilizer and water control ingredients offer the best general support
Shrubs and Trees
- Soil fortified with phosphorus and iron helps promote root development and prevents yellow leaves
- Using a soil that releases plant food can also help establish the strong roots these big plants need
- These plants don’t require a lot of water, so soil that contains ingredients to help increase water drainage and prevent soil compaction are best
Testing Your Existing SoilIt’s also important to double check your native or existing soil to see what you’re working with and to help understand the ingredients and nutrients you need to make your garden a success.
Not sure where to start? Here are the main things to look for:
Check the pHA soil’s pH level reflects its acidity or alkalinity and is measured on a sliding scale ranging from 0 (the most acidic) to 14 (the most alkaline).
Most plants grow best in a pH level that is between 6.5 and 7, but certain fruits, vegetables and grasses require a more extreme pH to bloom. Most existing or native soils ranges between 4.0 and 8.5. You can quickly and easily check your soil’s pH by using a pH test kit.
Soil CompositionSoil is usually made up of three components – clay, sand and silt. Too much or too little of any of these elements can make it difficult for plants to grow and thrive, so it’s important to make soil amendments as needed. Clay-heavy soil holds water well and compacts easily but can cause issues due to its density and high moisture levels. Sandy soils can drain quickly, but lack nutrients and moisture-retention.
To check the composition, wet a tablespoon of your soil and roll it into a ball:
- If it packs together and is mouldable, it has clay
- If it can be formed into ribbons, it has a high level of clay
- If the ribbon falls apart or feels gritty, it has a mixture of clay and sand
- If the soil can’t hold together at all, it has a high sand component
How to Make the Right Soil AmendmentsIn order to cultivate your native soil, it’s important to add the right ingredients in the right amounts to create the best environment for plants to grow.
CompostCompost refers to decomposed leaves, plant-based kitchen scraps, grass clippings, worm castings (or vermicompost) and other organic materials. It helps lighten heavy soils and adds nutrients to poor soil. You can purchase it in store or make it at home.
GypsumGypsum is made of calcium sulfate. It helps increase the calcium in soil, so it’s ideal for salty soils. It can also be used to loosen heavy or clay soil and to help improve aeration and drainage.
LimeLime can be used to raise pH levels to make acidic soil more alkaline.
ManureManure helps boost soil nitrogen, loosens heavy soil and improves water retention in lighter soils. Take care if you’re using fresh manure: the high level of nitrogen can burn plants, so be sure to compost it before using.
Peat MossPeat moss absorbs a lot of water and slowly releases it, so it’s usually used to help retain moisture. It can also be used to add aeration to clay soils or to add weight to sandy soils and help improve nutrient levels.
PerliteDerived from volcanic rock, Perlite is a mineral that shows up as the little white specks you see in most potting mixes. It’s used to increase aeration and drainage to help roots grow, and to prevent soil compaction.
SandSand can be added in high-wind areas to help hold plants in place or to make soil drier and looser, but is generally not needed.
SulfurSulfur has the opposite effect as lime: it helps to lower the pH in alkaline soil to increase its acidity. It also adds iron, which enhances water filtration and helps plants grown green and lush.
VermiculiteVermiculite is another volcanic mineral like perlite that helps boost aeration in soil. But dissimilar to perlite, vermiculite helps to retain moisture and fertilizer.
Now that you have a deeper knowledge of soil and soil amendments, you’re on your way to creating the lush, blooming garden you’ve always imagined! Shop our range of soil and potting mixes to find your ideal ingredients.