You may have heard about the miracle-working properties of sand as more and more people ditch traditional horticultural materials for simple builders sand in their garden. With promises of better drainage and improved native soils, you might be ready to make the switch too.
Builders sand, readily available at most home improvement stores and gardening centers, is an inexpensive way to improve drainage and aeration in garden soil. Used properly, you can incorporate coarse builders sand in everything from raised beds to potting soil mixes for healthier plants.
Sand does have its merit, but it’s not exactly the miracle-worker some would have you believe. And you can have too much of a good thing. Read on to learn more about builders sand and its appropriate uses in the garden.
What is builders sand?
Builders sand is a coarse building material, not to be confused with children’s play sand or even beach sand. Readily available at most home improvement stores and landscaping centers, builders sand is a cheap alternative to perlite, another horticultural material used to improve drainage and aeration in soil mixes.
Where to buy builders sand
Horticultural sand, horticultural grit, sharp sand, and builders sand are different names for the same coarse, gritty sand meant to add texture and drainage to growing mixes.
Since gaining popularity among gardeners and horticulturalists, builders sand has become commonly available at most garden supply stores. If not there, check your local Lowes, Walmart, or Tractor Supply. There’s even a greater range of coarse sands available with online ordering.
Why you should use builders sand
Most plants can’t stand to sit in water. Our favorite vegetables, herbs, and flowers all need proper drainage to grow and produce. Unfortunately, a lot of gardeners have rocky or clay soils that need to be improved before these plants will thrive.
Builders sand is an excellent alternative to perlite and vermiculite, two expensive horticultural materials that accomplish the same purpose. Take care not to confuse fine-grained sand for coarse builders sand, as play sand will cause more problems than it will cure.
When to use builders sand in your garden
This inexpensive coarse-grained sand has so many applications in the greenhouse and the garden. Just be sure to wear a mask when handling large quantities of builders sand, as it does contain silica, a lung irritant, and carcinogen.
Seed-starting mix
Seeds prefer to germinate in a lightweight, well-draining growing medium since some seeds will rot if exposed to too much moisture. Seedlings that stay overly moist are more susceptible to diseases like damping-off.
Penn State Extension recommends mixing one part peat moss (or coco coir) with one part sand (or perlite) to create a soilless seed-starting mix suitable for annual vegetables and flowers.¹
Sand, unlike peat moss, is also more apt to allow light to get through to those seeds that need some sunlight to germinate. Try covering your seedling tray with a layer of sand, rather than peat or compost, for better germination.
Sowing small seeds
Not only is sand essential in a seed-starting soil mix, but it’s a useful material to help with sowing tiny seeds. Mix your smallest seeds with a couple of tablespoons of sand and sprinkle the whole mixture over the area to be sown. For more tips on sowing small seeds, read this article on a few common seed-sowing hacks.
Potting soil
Larger plants and houseplants need good drainage, too – and builders sand has the added benefit of anchoring larger plants and plants with shallow root systems.
If you have the time to make your own potting soil, you’ll want to incorporate some sand into the mix so that your potted plants won’t be sitting in water. Here’s a sample homemade potting soil recipe from Penn State Extension:
- 1 gallon garden soil
- 1 gallon peat moss
- 1 gallon builders sand¹
Moisten the peat moss before you begin, and then mix three ingredients together until you have an even-textured potting soil. You can add more of any ingredient to get the consistency that you want – add more sand for succulents and cacti, or add more peat moss for vegetable and flower starts.
If you don’t need three gallons of potting soil, scale this recipe back to fit your needs–use a 1:1:1 ratio on all ingredients.
Propagating cuttings
Do you have any herbs or flowers that you want to propagate? Coarse builders sand is perfect for rooting cuttings.
To take a cutting, use a clean pair trimming scissors to cut a four to six-inch stem. Cut just above a leaf node to avoid hindering the growth of the mother plant. Leave at least two sets of leaves at the top of the cutting, but strip the rest of the foliage and set aside.
Fill a two-inch pot with moist builders sand, and use a chopstick to make a hole in the sand. Slip the cutting into the sand, leaving the foliage above ground. Keep the cutting moist, and between four and six weeks you’ll have a clone!
Improve native soil
Some gardeners are lucky enough to have naturally loamy soil–the soil type best suited for growing vegetables.
For the rest of us, we need to amend our native soil with additives to improve its texture and nutrition. Builders sand is a key component in addressing poor drainage in heavy native soils, but sand doesn’t work in all scenarios.
Luke Marion, of MIgardener, argues that the only time you should use sand in the garden is to balance out heavy compost. In this youtube video, Marion explains that sand will actually worsen drainage in clay soils, but adds air pockets and aeration to pure compost.²
If you do choose to incorporate sand into your native soil, put a thick layer of compost down first, followed by a layer of sand. Use a rototiller or a broadfork to turn the amendments in and loosen the soil for planting.
Storing root vegetables
Need an inexpensive and easy way to store root vegetables? Beets, carrots, and other root vegetables will keep for at least six months buried in builders sand.
To store root vegetables in sand, gently clean the roots and cut off their tops, and moisten the sand before you begin. Organize the roots by size and place similar roots together in plastic tubs between layers of sand, ensuring that no root touches another. Don’t try to store damaged roots–it’s better to enjoy them now than have them cause the other roots to rot in storage.
Transfer the tubs to a cool, dark place where temperatures won’t dip below freezing, and enjoy fresh root vegetables all winter long! For more information on long-term root storage, reference this article on storing beetroot, or this one for carrot storage.
In summary
A humble building material never intended for horticultural production, builders sand has its use in the greenhouse and garden. Incorporate builders sand into your seed-starting routine, add it to homemade potting soil mixes to improve drainage, or use it to store root vegetables in the winter. There is no shortage of uses in the garden for this inexpensive building material–perhaps you can come up with a few of your own!
Resources
¹ Sellmer, Jim, and Kelley, Kathy. “Homemade Potting Media.” Penn State Extension, Penn State, 22 Oct. 2007, https://extension.psu.edu/homemade-potting-media.
² Marion, Luke. “Applying Sand to The Garden – Friend or Foe?” MIgardener, 15 Aug 2016, https://www.youtube.com/watch?v=gL0lKS6O_5E&ab_channel=MIgardener.
