Came across an intriguing “study” (actually, more of a press release) about a company called To Soil Less that promotes using (their) gravel to trap moisture around plants…so, essentially, as mulch. From their website:
Welcome to a new age in gardening; Gravel Gardening. Yes, we have found a way to grow and sustain vegetables, fruits and flowering plants using nothing more than gravel, sand and cotton based fabric. The use of gravel in the cultivation of crops may represent the most resource efficient method of growing crops ever to exist. The ingredients are all natural and last a lifetime. Geological Agriculture is the process of growing fruits, vegetables and flowers in rock environments. Known also as geo-agriculture or gravel gardening, this method of cultivating crops enables vegetation to occur and sustain itself with limited to no use of soil and fertilizers.
Interesting…but not very practical, or necessary in the Northeast. Having lived in this region all my life, I have never seen anyone mulch with gravel, except in a “rock-garden” or in a house-plant. Whether or not you use a no-till method (a la Ruth Stout), it makes more sense to use a biodegradable mulch, like straw, newspaper, woodchips (for flower beds) and most importantly, start with good soil/compost. It ain’t rocket science!
However, I do think this gravel method has merit, especially for the drought-ravaged mid-west (and south). In the “study,” the folks at To Soil Less essentially planted a garden in a parched dust-bowl, covered the dirt with gravel and then didn’t water it manually at all. The condensation that happened under the gravel managed to produce (stunted, but alive) veggies. A solution to consider if other methods don’t/can’t work for you!
Photo of a gravel-bed lettuce seedling from the To Soil Less website