How to Make Your Soil Acidic for Blue Roses

Test your soil with a pH test kit before making any changes. pH ranges from 1 to 14, with 1 being highly acidic, 7 being neutral and 14 being highly alkaline. Roses like a pH level of around 6.5, which is barely acidic. To prepare your soil properly, you need to know where it is at the moment.

Add sulfur to the soil if it shows alkaline or neutral levels. Sulfur increases the acid in the soil. It takes several month for the soil to change, so you want to test and apply the amendment at least four months before planting the blue roses. You can also use natural material like pine needles or mulch to create more acidic soil. Till or mix in the amendment of choice with a tiller or hoe. The amount of sulfur you use is dependent on the size of the garden. Check the package for amounts. It is best to apply less than the recommended amount, especially if the soil is close to the 6.5 mark. You can always add more later.

Add lime to the soil if it is too acidic. Start the process at least four months before planting. Look at the recommended amounts on the package for the size of the garden. If you are close to the acid level needed, reduce the recommended amount to a quarter or less. Till it in the soil or use a hoe for small gardens.

Test the soil again a month before planting. Add a small amount of lime or sulfur, if needed, then wait for spring planting time.