How to Grow Altissimo Roses
This fragrant heirloom rose has been around since the mid 1960‘s and is a favorite in many home gardens because of its easy care and long blooming season. The Altissimo rose is a disease-resistant climber that produces large, single-petal, fragrant red blooms all summer long if cared for properly. Use these guidelines for planting and growing this show-stopping rose bush in your home garden.
Altissimo roses prefer a sunny location and well-draining fertile soil, and these growing requirements are easily met. Select a planting location that will receive at least 6 hours of direct sun each day, with 8-10 hours of direct sun being preferable. This delightful heirloom rose is hardy in growing zones 5 and above and is rarely bothered by pests.
The Altissimo rose is a climber and the planting location will need enough space for some type of structure for the canes to climb on. A mature Altissimo rose can reach up to 15 feet in cane length, but the bush can be kept pruned to any size desired.
The selected planting location may not have ideal soil, but that’s easy to amend. Even good soil will benefit from the addition of compost prior to planting an Altissimo rose bush. Start by digging a hole twice as deep and twice as wide as the rose bush’s container. Mix the removed soil with compost at the rate of two parts soil to one part compost. Backfill the planting hole halfway with the mix and lightly water the soil.
Planting a Container Grown Altissimo Rose
Carefully remove the rose bush from the container by slicing the container down opposing sides with a utility knife and gently pulling the container away. Hold the bush, roots facing down, over the planting hole and gently tap on the soil around the roots to loosen it. Unwind any roots that are wound around the root system and place roots and soil into the center of the planting hole.
Add or remove a little soil mix to keep the bud union at the level with the ground before backfilling the entire planting hole. When the bud union (knot where the roots and main bush stem meet) is at the right height, gently backfill the hole, firm the soil and water roots well to ensure there are no air pockets in the soil and all roots are in contact with the soil.
Planting a Bare Root Altissimo Rose
When ordering rose bushes from a catalog flower company, the rose bush will arrive in a ‘bare root’ stage. That term simply means the roots will be exposed and the rose bush will not be in soil nor a container. A bare root rose bush will need to be planted as soon as it arrives.
Prepare the planting hole and soil mixture a described above when planting a bare root Altissimo rose, but instead of backfilling the planting hole halfway with soil mix, create a cone-shaped mound of soil mix in the center of the planting hole. The tip of the cone of soil should be almost even with the ground surrounding the hole.
Set the rose bush on top of the cone of soil and gently spread the bare roots of the Altissimo rose bush over the cone of soil so they cascade down all sides of the soil cone. Make sure the bud union is even with ground level before backfilling the hole, then backfill with soil mix, gently patting soil on the roots to ensure they are all in contact with the soil. Water roots well.
Regular weekly waterings and a layer of organic mulch to help retain soil moisture and prevent weed growth are essential to keep the rose bush healthy and thriving.
Deadhead the spent blooms and prune away any diseased or dead canes as needed to promote new growth. Save severe pruning jobs until early spring.
Side dress with a balanced 10-10-10 fertilizer once in the spring.
Provide a trellis, arbor or other structure for the climbing Altissimo rose to adhere to and it will reward you with a multitude of large showy, fragrant red blooms from spring through fall.