When setting up your garden, you’ll have to decide on so many little details. These things include the layout of the garden, the location of garden furniture, and the plants you’ll be growing.
But before any of these decisions are made, you should find out the type of soil you have or intend to use. There are many types of soil for gardening, and each of them has its considerations.
Getting to know each soil type and how to best utilize it should make your garden as beautiful as it is bountiful. By the end of this, you should also be aware of how to improve soil quality and increase its fertility. So let’s jump right in!
What Types of Soil Is Good for Plant Growth?
Most agricultural experts and amateur gardeners agree that loamy soil is the best for plant growth. Loam is an almost equal mix of sand, silt, and clay. As you read on, you’ll find out how loam benefits from the properties of each of these soil types.
That said, different plants require different growing conditions. Depending on the kind of garden you’re growing, you might find yourself gravitating toward another soil type. For example, a rock garden will benefit from sandy soil, while a vegetable garden can use more clay soil.
Each type of soil has its strengths and weaknesses, and you can utilize any one of them to create a beautiful garden.
Types of Soil
Here’s a breakdown of each soil type and how to make the most of it:
Sandy
Sand covers around 900 million hectares of the earth’s surface. It’s mostly found in dry regions like deserts. The main mineral component of sandy soil is silicon dioxide, also known as quartz.
Properties
Sandy soil is dry, crumbly, and gritty. It’s lightweight and gets warm from sunlight quite easily. The pH value of sandy soil is low, making it acidic in nature.
The best attribute of sandy soil is its excellent drainage. The large particles forming the soil can’t cling to moisture that well, which makes it a great option for plants that require arid conditions.
The downside of sandy soil is the almost complete lack of organic matter, making it nutritionally poor for plants.
How to Amend Sandy Soil
You can improve sandy soil by upping its organic content, which you can do by mixing it with compost, manure, or other humus. This has the added benefit of improving the hydration level and allowing for better moisture retention.
What to Grow
If you want to grow flowering plants in sandy soil, you have more than a few options:
- Phlox
- Lavender
- Gazania
- Joe Pye Weed
- Black-Eyed Susan
If you’re more inclined to grow a vegetable garden, here are some culinary plants to choose from:
- Carrots
- Potatoes
- Radishes
- Cucumbers
- Rosemary
Clay
If you’ve ever played with plasticine when you were young, you probably know what clay looks like. It’s a type of soil made of superfine particles that clump up easily. Clay also sticks to your shoes and tools like there’s no tomorrow!
Properties
Clay soil is the opposite of sandy soil, meaning that it’s moist, clumpy, and homogenous. If the soil is made of 50% or more clay, then it’s described as heavy soil.
Although pure clay is devoid of nutrients, clay soil clings to microorganisms and dead plant matter. This makes it superior to other soil types in its humus content and ability to feed plants.
It also clings to mineral ions like calcium, potassium, and magnesium, which can elevate its pH rendering it alkaline.
The major downside of clay soil is poor drainage. If you have heavy soil, you’ll notice how water tends to pool on top of it instead of sinking to the bottom.
Clay soil can also get super hard when it dries out. This means it might impede root growth and cause plants to become root-bound if their growing roots fail to penetrate the hard soil.
How to Amend Clay Soil
Improving the texture and drainage of clay soil is as easy as mixing it with another type of soil that has larger particles. Adding silt, perlite, or vermiculite can help prevent soil compaction and aerate the soil with manual tilling.
You should also mix in organic material to enhance clay’s nutritional value and amend its alkalinity. Try adding peat moss, coco coir, or compost.
What to Grow
If you want to grow flowering plants in clay soil, you can choose:
- Iris
- Baptisia
- Aster
- Echinacea
- Coreopsis
If you intend to grow vegetables in clay soil, here are some options:
- Broccoli
- Brussels sprouts
- Cabbage
- Cauliflower
- Kale
Silty
Silt is the product of the wind, water, or ice chipping away at mineral rocks and transporting the resulting dust-like substance. The granule size of silt is roughly between that of sand and clay, which makes it a happy middle between the two soil types.
Properties
When dry, silt has a silky, powdery feel to it that leaves a film of dust on your fingers. Once moistened, it lacks the plasticity of clay and cannot be formed into one cohesive mass.
These properties make silt an excellent growing medium for many different crops. While it has a small particle size that can hold onto nutrients, it also drains water much better than clay does.
Just like sandy soil, the main component of silt is silicon dioxide (quartz), which contributes to its acidic pH.
That said, most silt deposits are quite shallow and can’t support the growth of deep-rooted plants. Silty soil can also form a hardened crust when it loses moisture, making it crackly and dry.
How to Amend Silty Soil
Amending silty soil can be done by loading it up with organic material. Vegetable compost, worm castings, and manure are all great ways to increase the nutritional value of silt.
Breaking up dry silty soil before applying organic amendments is crucial because wet silt is more difficult to mix evenly.
To decrease silty soil acidity, you can add lime or dolomite to bring up the pH. Just be careful not to overshoot it because it might render the pH too alkaline.
Lastly, you can cover silty soil with mulch to avoid moisture loss due to excessive drainage.
What to Grow
If you want to plant a flower garden on silty soil, you can pick:
- Rose
- Japanese barberry
- Smoketree
- Daffodils
- Snowflake flower
If a vegetable garden is what you’re into, you can plant:
- Corn
- Beans
- Squash
- Lettuce
- Onion
Chalky
Chalky soil is marked by the presence of an underlayer of chalk and limestone. They’re both forms of calcium carbonate that look like white rocks strewn around the field. The pH of these rocks is alkaline and they can contain chunks of flintstones that make them hard to till.
Properties
The main identifier of chalky soil is the presence of large chalk rocks under the layer of topsoil. The soil can be dry, hard, and shallow. However, it can also be deep and rich in clay, with the occasional chalk deposits showing up almost three feet under the surface.
Chalky soil is well-draining to a fault, losing moisture rapidly and retaining very few nutrients. It also has trouble providing essential nutrients like iron and manganese to plants, because they get locked up in the soil.
How to Amend Chalky Soil
Unamended chalky soil with high calcium carbonate concentrations isn’t ideal for any plant growth. So, figuring out how alkaline your chalky soil is can help you incorporate soil additives that bring down the pH to a suitable level.
Get a soil pH test kit and use it according to the directions. You’ll likely find the pH of your soil between 7.1 and 10, with 10 being the highest alkalinity. While you can’t turn chalky soil into an acidic growing medium, you can mix it with sulfur to improve its properties.
The most important thing to fix in chalky soil is the lack of nutrients due to the absence of organic material. Adding humus, compost, manure, and peat moss can elevate the nutritional value of the soil while also enhancing moisture retention.
To prevent water loss from chalky soil during spring and summer, cover the bases of your plants with a layer of mulch or peat moss.
What to Grow
If you want to plant something ornamental in chalky soil, consider the following:
- Queen Anne’s lace
- Dandelions
- Chickweed
- Goosefoot
As for culinary plants, chalky, alkaline soil can grow:
- Asparagus
- Beets
- Okra
- Oregano
- Yams
Loamy
Loam is the name given to the soil type that combines clay, sand, and silt in almost equal proportions by weight. It’s often touted as the ideal soil for almost all kinds of plants thanks to the properties of its components.
Properties
Loamy soil is a mixture of clay, silty, and sandy soils. It has the same ability to hold onto nutrients as clay soil but has much better drainage and a friable texture like sand or silt.
The pH of loamy soil can either be neutral or slightly acidic. Most plants prefer the pH range 6.0 to 7.0, which makes loam the right soil type to grow most crops
Loam can be found naturally, but is more likely to be made of an existing soil type by changing its structure with time.
How to Amend Loamy Soil
If you have deeply rich, well-draining, friable soil in your garden, then congratulations! You’ve hit the jackpot of soil.
Most of us who aren’t as lucky have to work hard to amend the soil to become loamier. Adding straight-up sand into clay soil or vice versa probably won’t turn it into loam. Instead, you’ll be left with a dry, hard substance that resembles concrete.
You can start by adding organic material, like peat, sphagnum moss, or grass clippings, and working it into the topsoil. Two inches of organic material can amend the top layer of the ground within a few weeks as the material decomposes. Using worm castings can also speed up the process.
What to Grow
As loamy soil is accommodating to almost all kinds of crops, you can grow the following ornamental plants in it:
- Wisteria
- Honeysuckle
- Rubus Tricolor
- Delphinium
- Magnolia
As for culinary plants, loam is a heaven-send! You can plant the following:
- Tomatoes
- Strawberries
- Wheat
- Sugarcane
- Pulses and legumes
How to Determine Soil Type
The first step to having a great growing medium for your garden is to know which soil type you have. There are a few tests you can do on your garden soil to determine its type and what you can grow in it:
Ball Test
Dampen a small portion of the soil in your garden and grab a small amount, balling it in your hand, here’s what to look for:
- Sandy soil should feel gritty and coarse. It should fall apart immediately and not form into a ball.
- Clay soil should feel slimy and coalesce into a ball that holds its shape.
- Silty soil should ball up but soften and lose its definition.
- Chalky soil should have little rocks or pieces of flint and not ball up well.
- Loamy soil should ball up but crumble and fall into a pile of dirt.
Baking Soda & Vinegar Test
If you suspect the presence of chalk in your soil but can’t find large enough rocks to confirm, you can do the vinegar test. Mix some of the soil into a half cup of white distilled vinegar. If the soil fizzes up, then you have chalky soil.
As for acidic soil, you can do the same test but with a quarter teaspoon of baking soda mixed into a half cup of water. If the soil fizzes on contact, you have acidic soil.
pH Test
Knowing whether your soil is acidic or alkaline can help you choose plants that fit the soil’s composition and meet the nutritional needs of your plants. Luckily, it’s as easy as getting a pH soil testing kit and checking the resulting number.
- A pH of 2 – 5: Highly acidic, might require liming to neutralize the acidity
- A pH of 6 – 7: Slightly acidic, the sweet spot for many plants
- A pH of 7 – 8: Slightly alkaline, a suitable pH for some plants
- A pH of 8 – 10: Highly alkaline, might require sulfur addition to neutralize the alkalinity
How to Improve Soil Fertility
Soil fertility refers to the amount of nutrition the soil can provide to growing plants to aid their growth without much human interference.
Any type of soil can be made more fertile by incorporating more organic material. Soil amendments like:
- Composted vegetables
- Composted animal waste
- Worm castings
- Peat or sphagnum moss
- Nitrogen, phosphorus, and potassium fertilizers
Can improve the mineral content of your soil and provide your plants with nutrients for growth.
You can also plant crops known for their nitrogen-fixing properties. These are called “green manure” plants, such as:
- Beans
- Clover
- Vetch
- Buckwheat
These crops restore the soil’s properties and prepare it for the following crop, giving you a much better yield.
FAQS
How do you know if your soil is poor?
Poor soil means a lack of organic substance in soil composition. It can be identified by noticing your crop yield; if you’re getting weak, puny plants from your soil, then it’s most likely depleted.
The texture of the soil is also telling, since poor soil compacts easily and has bad moisture retention.
What is the best soil for flowers?
As we’ve established, loamy soil is great for almost all crop types. However, flowers appreciate a sandy loam type of soil, which is slightly more acidic and has better drainage than regular loam.
Most flowers require frequent watering but don’t do very well in soggy, waterlogged soil. When water sits for too long and there’s not enough drainage, most flower roots, corms, or bulbs will rot and die.
Can I plant directly in compost?
While it’s not entirely far-fetched to want to plant directly in compost, it’s not recommended. Compost offers an amazing amount of nutrition for your plants, but it lacks the structure that supports growing roots. It can also have poor drainage, depending on its texture
You can sprout your seeds or plant small plants in compost before transferring them into a medium of both compost and soil. That way, you wouldn’t have to worry about leggy plants or bad drainage.
Conclusion
There are several types of soil for gardening with different properties that fit certain kinds of crops. Knowing the soil type in your garden can help you better understand its needs and how to amend it to get the results you want.
If you have clay or sandy soil, then you should mix them with organic material to aerate the former and compact the latter. Silt can be great on its own, but most likely requires additional mulching to retain moisture. As for chalky soil, you might need to mix in some clay to give it extra depth.
Loamy soil, on the other hand, is perceived as ideal for most crops. That said, you should keep an eye on its pH and nutrient levels to keep it in tip-top shape.
Last but not least, growing green manure crops can help you restore nitrogen reserves and prepare the soil for the following crop.