Loamy, well-draining soil is the best soil for roses. These plants suffer from wet, soggy roots, and drainage is important to prevent root rot and other issues. Roses prefer a slightly acidic environment, and most commercially-available rose amendments will provide the right pH. Compost is another good way to acidify the soil just the right amount. Shrub roses and climbing roses can generally handle rocky or poor-quality soil a little better than other roses, but they still prefer a bit of enrichment with compost or peat moss.