No, I’m not Rumplestiltskin, the cranky gnome in a Grimm fairy tale; I can’t spin straw into gold. But, straw saves me money, crops and my sanity, which is golden to my thinking.
Everything in the vegetable garden is mulched with a 6-inch layer, including blueberries, Alpine strawberries and cranberries. I use a foot or two of straw atop the potato bed to grow clean potatoes that can be easily harvested. Tubers form in the straw and crops are always bigger when I use the straw mulch.
First, let me explain the difference between straw and hay. You don’t want to use hay, as it will cause nightmares and plenty of weed pulling. Hay is grown for animal feed and contains protein-rich seed heads that when spread over gardens sprout. They quickly grow into lanky, seedy plants that are difficult to control by either pulling or spraying.
Straw is the bottom half of hay stalks and contains few or no seed heads. It’s pure carbon and has no protein. Straw stalks are hollow and don’t compact or mat. They’re also slow to decompose and don’t tie up nitrogen or other nutrients in soil, making the perfect mulch.
Potato crops are huge when grown in a foot or two of straw on top of the soil. The blueberries in the background benefit from straw mulch, because their roots are shallow, and the plants are moisture lovers.
A bale of straw costs about $4 in my area. I get it from a farmer nearby. Numerous garden centers stock straw, too. Bales are huge; one will usually cover the garden. Just be sure that you are buying straw, not hay.
A thick blanket of straw keeps the moisture in soil, slowing evaporation radically. Watering the garden once a week will be the norm, rather than every day or two. If you live in an area of the country that is experiencing rainfall shortage this summer or drought, straw mulch is gold! I do. We’ve received only a tenth of normal rainfall and had a huge snow deficient last winter. The ground is so dry, it’s cracking in spots. But, I water the vegetable garden only once a week, despite high temperatures and lack of rain.
Straw also saves crops like tomatoes, peppers and squash from developing blossom-end rot and cat-facing; blueberries from shriveling; and sweet peppers from turning hot. Soil moisture stays even and calcium can be transferred from the soil to tomatoes easily, preventing the diseases. Straw mulch at the base of tomato and pepper plants also prevents that transfer of soil-borne diseases such as early blight to plant leaves. No water splashes up from the soil to leaves, because the straw absorbs it.
A thick straw mulch also fosters the growth of large pumpkins, winter squash and watermelons. The mulch provides a clean blanket upon which melons and pumpkins can grow unblemished.
Have you used straw for mulch? What other materials do you use to hold moisture in and prevent diseases?
Doreen Howard has written for The Old Farmer's Almanac All-Seasons Garden Guide for 15 years and is the former garden editor at Woman’s Day as well as a photographer. She has grown more than 300 varieties of heirloom edibles and flowers in the last two decades.