Soil Supercharge: Elevate Your Garden's Potential with Proper Soil Preparation

When people refer to gardening as “playing in the dirt,” they aren’t kidding. Yes, gardening calls for placing plants in soil and caring for them there, but you can also expect to spend a fair amount of time working with the dirt itself. 

Before you plant one seed or seedling, you should take steps to make sure its soil will provide what it needs to grow and thrive, from adequate nutrients to room for airflow. This process, soil preparation, is a must for successful gardening, particularly when you’re growing food.

“It's not really the most fun that you can have in a garden, but I would argue that it is the most important thing you do,” Vego Garden horticulturist Sydney Fiene said. “Soil is the root of your crops, quite literally, it’s the base. If your soil isn’t thriving, then your veggies will not, either.”

Stocking the Pantry

When you prepare soil, you’re creating a welcoming home for the plants that will live there, complete with a fully stocked pantry. How do you do that? It depends on where your garden is.

For gardens in raised beds, for example, Fiene recommends layering soil with recyclable materials like branches and cardboard that will slowly decompose over time.

“This will create an organic soil mixture with the perfect balance of nutrients plants need,” she said.

Fiene speaks from experience. At the Vego Garden farm, the horticulture team uses a cost-effective soil preparation method known as Hugelkultur, which calls for building raised beds on top of decaying wood and organic matter to provide a long-term supply of nutrients and encourage good water drainage.

“With this method, you’re layering large sticks or logs; adding your cardboard, your leaves; and then on top, adding your finishing soil (high-quality, nutrient-rich soil mixture) and your compost,” Fiene said. “It keeps it (your raised bed) filled for a long time.”

That said, with layering, you should expect the soil to lose volume from year to year as the organic materials decompose. With that in mind, Fiene likes to refresh the soil’s top layer each year with organic compost, finishing soil, organic fertilizer, and earthworm castings (worm manure). That builds the soil up and provides extra nutrients for the plants.

Remember that soil prep varies by setting. If you’re planning to grow vegetables from the ground, you’ll have a more extensive set of to-dos than you would for raised beds. 

“If you’re using two-by-fours to make a little box to fill with soil, you can absolutely do that, but the soil underneath is probably thick, sandy, or out of nutrients, because it’s been sitting there for years,” Fiene said. “You’ll have to turn the (ground) soil to make it easier to plant — and so the roots can reach further down. On top of that, you’ll have to add more compost and more finishing soil to make sure that you balance out your nutrients.”

Harmony in the Soil: pH Balances

Even if your soil is packed with nutrients, your plants may not be able to fully absorb them if the soil’s pH level is off. The pH balance of soil refers to its acidity or alkalinity level, measured on a scale from 0 to 14. Different plants thrive in different pH ranges. In soils that are too acidic or too alkaline, certain essential nutrients may become less soluble — and less accessible to plants.

“If your soil is too full of alkaline with a pH above 7.5, or too acidic with a pH below 5.5, it can make a big difference in what kinds of nutrients are available to your plants,” Fiene said. “Maintaining an average, maybe 6 or 7, increases your chances of getting better growth.”

So, what do you do if you test your soil and find it’s too acidic or too alkaline? Consult with your local farm supply or gardening store. Most carry products that help you achieve the balance you need.

Organic Matter’s Superpowers

Not only will your plants’ roots need easy access to the food you’re providing, but they’ll also need some breathing space and regular drinks of water. The good news is, when you add organic matter to your soil, you’re helping with those things, too.

“Over time, organic matter actually improves the soil aeration, water infiltration, and nutrient-holding capacity,” Fiene said. “It also helps with the structure of the soil that you're aiming for. You don't want it to be super packed down because the roots aren't going to be able to breathe or get any water.”

Another thought about water: Plants need water but give them too much, and you jeopardize their health. So, don’t overdo the watering, and watch your soil to make sure it’s draining properly.

“If water going to to the side of the pots or the side of your beds, rather than actually touching the roots, that can cause a lot of serious damage to your plants,” Fiene said. 

Additional signs of drainage problems are plants that are not thriving, mold, and unpleasant odors. To improve drainage, Fiene said, you can add generous portions of organic matter like compost, shredded leaves, sticks, or even kitchen scraps. 

Fiene suggests working organic material into soil and turning the soil over routinely between plantings. If you need to add organic material after you’ve planted, add it to the top of the soil and gently it mix with your hands, but don’t work it in deeply.

Offer a Comfy Blanket

While topping your soil with mulch is not necessarily the most critical aspect of soil preparation, it does help you provide optimum conditions for your plants. Because it minimizes evaporation, it allows you to water less frequently.

When temperatures drop, it provides insulation that keeps plants’ roots warmer. 

And, as mulch decomposes, it provides even more nutrients and improves soil’s ability to hold water.