Why mulch should be added underneath your Garden Grid™
Easier plant spacing. Keeping mulch below your Garden Grid™ leaves each square visible, so you can use it to space plants correctly. Whether you’re planting a new crop or replacing plants that have finished producing, your planting guide stays easy to see. Use our square-foot gardening plant spacing guide to see how many plants fit in each square.
Better watering coverage. Placing mulch on top of the Garden Grid™ can block some of the water flow and make it harder to see if your plants are getting watered evenly. By mulching underneath it, you can see that all your plants are getting enough water. Check beneath the mulch afterward to make sure the water is reaching the soil.
Helps keep mulch in place. Lightweight mulch, such as straw, can blow around in windy weather. Resting your Garden Grid™ on top helps hold it in your bed, so less ends up scattered outside the garden.
How to add mulch around growing plants
Start with a weed check. Pull existing weeds before spreading mulch around them. No need to give them a cozy new blanket.
Lift carefully. Gently raise the Garden Grid™ enough to tuck mulch underneath, working around established plants without pulling on their stems or roots.
Spread an even layer. Start with roughly 1-3 inches of loose straw or shredded leaves, then adjust for the material and conditions. You want to avoid creating a dense, soggy mat. Keep a gap around stems and crowns, and leave newly sown spaces clear so seedlings can emerge.
Set the Grid back on top. Keep the tubes and water outlets clear. Run the water, watch its coverage, and check beneath the mulch in several squares.
Check before watering again. Mulch can slow moisture loss, so the soil may stay damp longer than it did when bare. Let the soil guide you rather than keeping the same schedule out of habit.
What are the benefits of adding mulch to your garden?
Helps soil hold moisture. Mulch shades the soil and reduces moisture lost through evaporation, helping it stay moist longer between waterings.
Helps regulate soil temperature. Mulch acts as an insulating layer for your soil, slowing heat transfer between it and the air. It helps soil stay cooler in hot weather and hold warmth when temperatures drop, cushioning roots against sudden temperature swings. It won’t prevent plants from eventually getting too hot or freezing if extreme temperatures persist for long periods of time (days or weeks), but it slows the process and helps mitigate unexpected temperature swings.
Reduces weeds. Mulch blocks sunlight from reaching the soil surface, helping suppress weed growth.
Helps prevent soil-borne disease. Soil can harbor disease-causing organisms, including fungal spores. When rain or overhead watering splashes soil onto leaves, it can carry those organisms to your plants and spread disease. Mulch covers the soil to help reduce that splash, while your Garden Grid™ waters at ground level rather than spraying down from above. Together, they help reduce a route by which some plant diseases spread.
Improves soil quality. Natural mulches, such as straw and shredded leaves, gradually break down and add organic matter to your soil. This helps improve soil structure, supports beneficial soil organisms, and helps the soil hold moisture and nutrients.
Which mulch should you choose?
Best bets: clean straw and shredded leaves
Clean straw. Straw is what we use in the video above. It’s lightweight and easy to spread around vegetables. Look for a clean source with as few seeds as possible. Seeds mixed into straw can sprout in your bed, adding unwanted plants and more weeding—the opposite of one reason you’re mulching.
Shredded leaves. Fallen leaves can be a handy, free mulch. Rake them into a pile or collect them with a mower’s bag attachment, shredding them as you go. Smaller pieces are easier to spread and less likely to form a thick mat than whole leaves. Spread them loosely, and fluff or thin the layer if it packs down.
Skip: hay and fresh grass clippings
Hay often contains seeds that can sprout in your bed and create more weeding. Fresh grass clippings can form a dense mat when piled deeply.
Do I need to add mulch to my garden?
Nope! We’ve grown plenty of gardens without it. Use it when it makes tending your garden easier, and skip it when bare soil suits your setup better.
A greenhouse changes the conditions, but it doesn’t make mulch automatically unnecessary. Soil can still dry out, weeds can still grow, and temperatures still need monitoring. Choose based on what your bed needs.
