What soil composition ensures optimal rose growth?

The ideal growing medium for roses includes loam, organic compost, and materials to assist drainage, such as perlite. Loam is a rich soil type with a sand-silt-clay ratio of 40-40-20 that supports root systems as well as provides an exchange of air. Compost serves as a food source for microbes found in soil that help fight diseases. Drainage materials prevent the over-saturation of soil, which is most commonly responsible for root rot in heavy soils.

Test your soil's pH every spring! I buy a $12 kit at local nurseries that works just fine! For home gardens, that is accurate enough! Most roses utilize iron and phosphorus best at pH 6.0-7.0. If the soil tests are too acidic, add lime! Are the results showing too alkaline? Then you should mix in sulfur or peat moss. Adjustments usually take 4-6 weeks to establish.

Utilize expanded shale (3-8mm sized particles) in clay soils for better drainage. A client in Louisiana was able to reduce root rot by 80% by using this soil amendment. Coconut Coir, in sandy soils, holds 8 times its weight in water and should be soaked overnight before mixing into beds.

Don't try to reuse rose soil without sterilizing, aka baking, it at 82°C (180°F) for 30 minutes to eradicate pathogens. Better yet, annually replace up to 50% of the soil with a fresh moistened compost loam mix. You will be rewarded with deeper rose colors and fewer pest problems.

Read the full article: Best Soil for Roses: Expert Tips for Lush Blooms