Preparing the ideal soil for your roses
After you've determined where to plant your new roses and dug the planting holes, it's time to prepare the soil. (If you haven't found the perfect spot for your roses yet, I recommend reading my Hub on that topic).
Soil is the foundation on which your roses will either stand or fall. This can not be understated. Preparation of the soil is 90% of the work. So any skimping here greatly reduces your future bouquets.
The ideal rose soil mixture consists of 50% organic material (rotted manure, humus, or compost) and 50% inorganic material (sand, silt, and clay). To get this mixture, I recommend buying a large wheelbarrow or garden cart and get ready to mix. When blended together in proper proportion, your soil should have the consistency that when wet is not too muddy and when dry, not too hard. This soil type is known as loam. And achieving the ideal loam soil is a goal all of us amateur rose gardeners strive to achieve.
For ease of reading and flow, this hub will be organized into short sections; each beginning with a question. Ready? Let's amend some dirt!
Time To Amend Your Soil
When is the best time to begin preparing (amending) your soil?
The ideal time to get going on your soil mixture is 3-4 weeks before planting your roses. Here in the Midwest, that time frame is the 2nd or 3rd week of March.
What products should I buy to obtain the proper soil mix?
- Rotted or decomposed compost
- Rotted or decomposed animal manure (horse or cow is most plentiful)
NOTE: Don't skimp on the manure. Roses LOVE this stuff and quality manure is a MUST!
- Organic humus
- Non sphagnum peat moss or mushroom compost
- Indigenous soil obtained from digging your holes
- Silt (can be purchased as river dirt or silt)
- Clay (pelletized is best) if available
What is the proper proportion of these ingredients?
- 1 shovel of compost
- 2 ½ shovels of manure
- 1 shovel of humus
- ½ shovel of peat or mushroom compost
- 2 shovels of indigenous dirt
- 2 shovels of sand
- ½ shovel of silt
- ½ shovel of clay (if not available, substitute with indigenous dirt)
Mix these ingredients together in your wheelbarrow and after you think you're done, mix a little more. How much you'll need depends on how many plants you need to provide for. -- When properly mixed, this soil blend will provide the near perfect environment for ideal bacterial growth and nutrient absorption. And now you're ready to test your soil for pH.
Test Your Soil For pH
Why do I have to test the soil for pH?
Roses need a proper pH to thrive. This pH range is between 6.0 & 6.9, or slightly acidic. The desired pH for roses is 6.5.
How do I test for pH?
The simplest way to test the pH of your soil mixture is to take a fair sampling of the soil (enough to fill 50% of your 2' x 2' hole or approximately 4 square feet), add a small amount of water (enough to dampen but not saturate), wait a day, and then test. pH soil tests are available at almost every local garden center. I would purchase one that allows for multiple tests as needed.
Test your work and wait for good results. If the pH is slightly out of range, here are some tips to bring levels within tolerance.
If the soil is too alkaline, 7.0 or above, how do I lower the pH?
To lower the soil's pH, the quickest way is to add ammonium sulfate (a sulfur product). Ammonium sulfate is desired due to its ability to work immediately after watering in.
How much ammonium sulfate do I need to add?
Desired pH: 6.5
Current pH: 8.0 Add: ¾ ounce per 4 square feet
Current pH: 7.5 Add: ½ ounce per 4 square feet
Current pH: 7.0 Add: ¼ ounce per 4 square feet
If the soil is too acidic, 5.9 or below, how do I raise the pH?
The easiest way to raise the soil's pH is by adding crushed limestone.
How much crushed limestone do I need to add?
Desired pH: 6.5
Current pH: 5.0Add: 2 ¼ ounces per 4 square feet
Current pH: 5.5Add: 1 ½ ounces per 4 square feet
Current pH: 5.9Add: ¾ of an ounce per 4 square feet
Do I have to retest after adding the ammonium sulfate or limestone, and when?
Yes, but you'll need to wait 1 week to do so. If the soil is still out of tolerance after 1 week, amend accordingly and test again. This is one of the reasons you need to start this process 3-4 weeks before planting. If for some reason you're still baffled with out of range results, I suggest calling a local garden pro center for additional advice.
And that's about it on how to prepare and amend your soil, the foundation, of your future bouquets of rose's splendor. Any questions please feel free to comment. Good luck and get ready to smell the roses.
Next installment: Planting your roses!
- Soil Test Kit and soil information by Heirloom Seeds
Soil test kit for the home gardener.
- Jackson and Perkins
Quality Rose Selection