LOAM SOIL: Standard loam soil – composed of 40% sand, 40% silt, and 20% clay – is the ideal soil for gardening and growing vegetables especially.
The concentration isn’t set in stone however: the proportions of sand, silt, and clay can vary resulting to variations of loam soil. These include silty loam, sandy loam, sandy clay loam, and silty clay loam, containing 10% sand, 70% silt, and 20% clay.
Clay soils are known for being dense and having good water and nutrient retention characteristics. This makes the soil a good medium for growing flowers and plants with demanding watering requirements.
Sandy soil, on the other hand, is the choice for plants that can handle the summer heat like cacti, tulips, shrubs, and other plants that don’t need a lot of water to thrive.
Outside of desert plants however, sandy soil isn’t a great soil on its own because it doesn’t have good water and nutrient retention like clay soils do. On the plus side, its good drainage means the soil warms quicker than others, allowing gardeners to start working on their garden sooner.
And then there are silty soils whose particles are smaller than sand but larger than clay. While not as fine as clay, silt can hold moisture and nutrients well, but it also has the tendency to get compacted when under constant pressure. Known to be more fertile than other soil types, it’s no surprise that coloured flowers, grasses, vines, and other plants thrive in moist soil that’s high in silt content.
Loam soil is the result when you combine silt, sand, and clay, carrying the best characteristics of all 3 soil types and allowing gardeners to grow just about any plant or tree they want.
Having loam soil in your garden means you don’t have to amend and add too much to the soil. The clay and silt particles allow loam soil to retain moisture and nutrients, while the sand particles ensure that the ground doesn’t get easily compacted and waterlogged.
It has all of the strengths of 3 soil types but without their weaknesses, making loam the ideal gardening soil regardless of the season: it doesn’t dry under the summer heat like sand nor does it get waterlogged during winter like clay.
Unsurprisingly, fertility is another trademark of loam soil – moist, loose, and teeming with organic matter and healthy microscopic organisms that help optimise nutrient cycling for plants. Loam soils are usually filled with decaying insects and plants, which can only help enrich the soil.
These decaying organic matter are broken down slowly but surely – releasing nutrients into the ground for your garden plants to feed on.
Worms and other friendly critters, on the other hand, move through the ground – mixing the soil and creating water passages as they go their way. This ensures that the plants have a good base to grow in – one that drains water well but retains enough moisture and plant food for healthy growth.
So how can you tell if you have loam soil?
Distinguishing loam soil is quite easy with its rich and dark brown appearance. If you pick up a handful of loam soil, it’s usually moist and can be easily rolled into ball – but easily crumbles upon touching when the correct proportions of silt, clay, and sand are present. You can also run water over loam soil. You’ll notice that while it drains the excess water easily, it still retains its trademark moisture.
Loam is the best soil for gardening, but that doesn’t mean there’s nothing you can do to improve it. After all, while a soil may have all the best properties of sand, silt, and clay, it needs to provide more than that. Your garden soil also needs to have the right nutrients at the right amounts to keep garden plants in tip-top shape.
To find the right supplements for your soil, you need to determine the nutrients your loam soil contains and how much of each.
A gardener needs to turn their attention to three things to answer the questions above:
The mineral sources and organic material in the soil
How much the soil has eroded and weathered
The amount of nutrients consumed by the plants that previously occupied the space.
Fortunately, while plants need many nutrients to survive and thrive, you don’t have to keep tabs on all of them and focus only on the major plant nutrients – nitrogen, phosphorus, and potassium or NPK for short.
Chemical fertilisers are available to give your loam soil a nutrient boost, usually labeled with 3 numbers, each representing the percentage of NPK they contain. But keep in mind that chemical fertilisers don’t provide more than NPK.
True, they are less expensive than natural fertilisers for short-term results since chemical fertilisers dissolve easily, giving your garden the quick boost it needs. The downside, however, is that these fertilisers also drain out of the soil easily.
Natural fertilisers, on the other hand, have more to offer as far as plant nutrition is concerned, containing NPK along with several trace elements and micro nutrients that plants also need – although in smaller amounts.
The issue with natural fertilisers though is that it’s impossible to get NPK in precise values, which varies from one source to another. If you plan to use natural fertilisers for enriching your loam soil, you may want to consult a gardening book that lists various NPK sources along with their average values.
Fertilisers from natural sources also prove to be more cost efficient in the long run than their chemical-based counterparts.
Natural fertilisers are made of organic material, broken down to release nutrients overtime. While it doesn’t give plants a quick boost, the natural process ensures that nutrients are not wasted and washed off the soil.
All this talk about NPK shouldn’t worry you if you add compost at least twice a year, keeping the humus level in your garden healthy.
However, if you want to further build up your soil’s fertility, giving your plants and garden an NPK boost every now and then is in order. You want to apply fertiliser to your loam soil when the plants develop leaves, next when they begin to bloom flowers, and finally when the plants start bearing fruits.
PROS AND CONS
What’s Nice About Loam Soil
Loam is the most popular soil for gardening and agriculture, and for good reasons. Its balanced mixture of sand, silt, and clay makes the soil well-aeriated and drained while retaining enough moisture and nutrients for plants to feed on. Good loam soil also allows for ideal root penetration as the sand particles keep the ground from being too tightly packed and dense.
The pores between soil particles are responsible for water retention – and soils with finer particles have more spaces and greater water retention. When the ground is watered, most of the water moves downward, continuously and almost immediately after irrigation due to gravity.
However, water is also logged in the pores between soil particles – almost filling the entire space. keeping the soil moist long after watering. Since loam soil has fine silt and clay particles, it can hold water better than sandy soil.
Good drainage is one of loam soil’s positive trademarks. Without good drainage, soil can easily become waterlogged – suffocating the roots of plants because of insufficient aeriation and causing root rot. Loam soil, however, has only 50% of its soil pore space occupied with water – ideal according to experts.
When gardeners are working with other soil types, amending – the process enhancing soil quality by adding organic and inorganic materials – is a must, and gardeners usually steer clear from heavier, unamendable soils. Loam soil, however, is easily cultivated and generally rich in nutrients. Keep in mind though that there are variations of loam soil, those that have higher amounts of clay or sand, may need amending depending on the concentration.
What’s Not So Nice About Loam Soil
The right combination of the 3 main soil particles give loam an excellent structure, making it easier to work with than other types of soil. That said, loam soil not without disadvantages.
Erosion is one of the main issues with loam soil. While it retains water easily, moisture doesn’t penetrate the soil well enough to increase its density and bulk. Loam soil particles are prone to detaching especially when disturbed by rain, strong winds, and even day-to-day activities – washing or blowing away silt and clay particles and leaving behind sand particles notoriously known for being very light.
As far as plant variety is concerned, loam soil can accommodate almost every plant…almost. If you plan to grow plants or shrubs that prefer sandy, free-draining soils (like cactus and other desert plants), loam soil may be too fine, heavy, and drains too slowly for the plant roots.
This woody perennial has over 100 species and boasts thousands of cultivars. Roses can turn into erect shrubs – growing climbing stems that have sharp prickles. However, what made roses world-famous are its beautiful flowers. While the flowers vary in shape and size, they’re often large, spectacular, and boast a wide range of colours.
Many think that tomato is a vegetable, but botanically speaking, it’s a fruit. One can’t deny, however, the near-endless culinary uses of its red, juicy berry.
Not to mention tomato is rich in lycopene whose list of health benefits is also impressive. Tomatoes thrive with moist, soft, loamy soil as their roots tend to go deep.
Its flowers are mainstays of flower shops, commonly used as filling for corsages. The plant can grow up to 1.2 meters tall with its branching stems teeming with tiny white, pink, or purple flowers hence the name.
It’s an excellent plant for decorating borders, rock formations, and other points of interest in your garden.
It’s not just one of the most cultivated vegetables in the world, cabbage is one of the healthiest foods too! The leafy vegetable belongs to the same family as kale and broccoli, and it grows best in heavier loam soils with higher silt or clay percentage.
It’s an excellent source of essential vitamins and low in calories too.
This vegetable has been extremely underappreciated especially on the internet, with many memes making fun of it. However, broccoli, which thrives in heavier soils like its relative above, is a powerhouse of health benefits.
It’s rich in protein, can help lower bad cholesterol, and has positive effects in the body’s detoxification process.
Contrary to broccoli and cabbage, carrots require loamy soils with higher sand percentage.
Growing carrots require patience but a good harvest will prove worth it: this member of the parsley family has numerous culinary uses and is a rich source of potassium, carotene, vitamin A, and nutrients.