Rose Replant Disease

If you speak to any experienced gardener about roses, many will tell you that you can't plant a rose where one has previously been grown. This is absolutely true but there are things you can do if needing to replace a single rose or rose bed to help new plants survive.

What is Rose Replant Disease?

Rose replant disease is a general presentation of ill health and plant failure if a new rose is planted in the same soil where a previous rose was grown. Over the years a lot of research was done to understand the issues that may cause the issue and as recently as 2020 novel research papers have been released looking into the underlying causes.

These research papers found that a combination of fungal & Microbial infections cause rose replant disease by attaching new roots from the plant. During the research it was found that older more established plants are able to tolerate these microbes without impacting plant health.

Replacing the soil

The traditional way of solving rose replant disease is to dig out and replace all the soil in the affected area / bed and replace with clean, fresh soil (either topsoil or from elsewhere in the garden) to allow you to plant the roses in the old rose bed. While still effective today, this is the most labour intensive, requires the most compost / soil and for most isn't something that is feasible.

Plant in a cardboard box

At Henry Street, our tried and trusted method of replanting roses is to plant any new roses in a cardboard box around the size of a 6 bottle wine case filled with fresh compost. This method works by allowing the new rose's roots to remain completely isolated for the first 2 years in the ground away from the infected soil. Only once the rose has been in the ground 2 years will the cardboard box start disintegrating and allowing the new roots into previously infected soil. At this point the rose is already established and able to tolerate the microbes in the old soil.

To do this method, you'll need to leave all 4 sides and the base in tact only removing the top of the box. Dig a hole in the rose bed the same size as the box and place the box inside and fill the box with fresh compost. Plant the rose in the new compost and water in well.

Use Empathy Mychorizal Fungi

Some people in more recent years have suggested that by planting roses with a full treatment (around 30g per plant) of mychorizal fungi you can plant a rose in old infected soil. From our experience this is a better method than planting roses straight into old soil with no treatment but isn't as reliable as planting a rose in a cardboard box of fully replacing the soil.