1 of 10
Soil isn’t made up of just one component, but many. Learn about the basic elements below, then incorporate them in the recipes that follow.
Each of these provides plants with the nutrients necessary for growth: nitrogen (N), for making leaves; phosphorus (P), for forming flowers, fruits, and seeds; and potassium (K), for building strong roots.
From top down:
The “be-all-end-all” for soil health, compost not only increases fertility but also improves soil structure so the mix holds water effectively.
Sold in granular form, organic fertilizer enriches the soil with a balanced blend of NPK, providing micro-organisms with a nutrient boost.
Made of pine or hemlock, it increases soil’s fertility as it decomposes.
2 of 10
Most plants prefer good drainage. These add-ins create air pockets that collect—and release—water.
From top down:
Also known as calcium sulfate, gypsum helps clay soil aggregate into larger particles. It has a neutral pH but does affect soil chemistry, so use it sparingly.
A fired igneous rock that looks and feels like tiny bits of Styrofoam, it is lightweight and affordable.
Coarse is the key here. Look for horticultural-grade or river sand. Don’t use masonry or fine sand, which will turn your soil into cement!
Sold as inexpensive kitty litter, this fragrance-free, nonclumping clay works best in heavy soil.
This insoluble crushed rock is available at local feed stores. Its small size and durability make it suitable for all container sizes.
3 of 10
Containers dry out fast in warm weather. So include one of these to keep soil hydrated but still light and fluffy.
Best for sandy blends, this heat-expanded silicate mineral contains spaces that hold water.
A sustainable substitute for endangered peat moss, coir is made from coconut fiber. This type, sold as compacted bricks that break apart, is best for general potting soil.
It provides extra water retention—excellent for tropicals and other plants that prefer moist, wet conditions.
These super-absorbent crystals hold 200 times their weight in water, which is then released slowly as plants need it.
4 of 10
Like top chefs, pro gardeners add “magic” ingredients to enhance their potting mixes, including trace elements that are beneficial to plant growth.
Clockwise from left:
It controls odor and improves drainage.
Often used by biodynamic gardeners, granite, quartz, or schist can help replicate native soils.
Packed with minerals such as magnesium, potash, and iron, this oceanic sediment increases fertility by improving soil chemistry.
5 of 10
Soil Boosters, continued
High in nitrogen, this ingredient, made from dried blood, works best for foliage plants.
Dried and ground seaweed provides plants with nitrogen and potassium, as well as trace elements that enhance growth.
High in phosphorus, it provides key nutrients for flower, fruit, and seed development.
This by-product of the cotton industry slowly releases nitrogen, phosphorus, and potassium into the soil while also increasing the acidity of the mix.
6 of 10
All-purpose soil mix.
Swipe here for next slide
7 of 10
8 of 10
For woody plants and perennials.
9 of 10
10 of 10
Popular in Gardening Ideas and Tips