When and How Much to Mulch the Garden You can.

Jul 26, Gravel Mulch for Roses I use ¾ inch (2 cm.) gravel mulch called Colorado Rose Stone around nearly all of my rose bushes. The gravel mulch is knocked by some, as they say it will make the root zone too hot and kill off the plant.

Similarly, hay contains too many weed seeds, and straw decomposes quickly and needs to be replaced frequently.

I have not found that to be the case in my climate here in northern Colorado at all. Oct 30, Mulching around your roses protects them from weeds and keeps the soil from drying out. For the best results, you should use a 2- to 3-inch layer of organic mulch around your roses. You can apply mulch to your roses any time of year but it is best in early spring and then again in late summer to early fall.

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A 2” layer would be considered the minimum application, but a thicker application will need to be applied less often. We suggest a layer of 2”-4” for best results. Apply a ″ layer of your chosen mulch around the base of the rose, spreading it to the width of the rose canopy. For your mulch material we recommend using a good quality garden compost, composted straw or bark, or well rotted manure from a local farm (manure must be at least 2 years old, as fresh manure can burn the roots of your roses).

The best time to apply mulch is in early spring, about the same time you remove winter protection. In areas with warmer winters, apply mulch just before your roses start to leaf out and before weeds start to sprout.

You can apply mulch anytime, and you usually need to replenish it every two to three months.