Disease tolerant roses

Read more from Hayden Foulds

By late summer/autumn, I know many people are ‘over’ roses. You know what I mean – few flowers, no leaves left and just a bunch of sticks in the garden. It is way too early for the winter prune so they just get left there looking miserable or even worse, get the spade treatment in favour of something else getting planted.

I know many people also don’t like to spray for a wide range of reasons from time and cost through to health and environmental reasons. I hate spraying and try and do as little as possible, usually only a winter clean up spray or two but that’s another column.

Paddy Stephens, Iceberg and Glorious RosesIs it possible to have a garden of mostly healthy roses for most of the growing season?  

Yes it is, provided you do a few basic things. I must also add that no rose is never 100% free of pests and diseases no matter what you try. So there will always be a few spotty leaves to contend with.

Provide the basics for your plants

As with anything, plant or animal, if they get stressed, they get sick. So water and feed your roses, prune them in winter, remove the old flowers during the growing season and grow them in a situation suitable for them – plenty of sunshine is the most important factor.

Choose the right roses for your region

There is a wide range of varieties out there and it is important to choose the right ones that have good disease tolerance. The best way of doing this is see what is doing well in your area as it may not do so well in other areas. So visit your local rose garden and walk the streets to see what is performing well. Your local rose society is also a good place to seek out recommendations. I once did a survey of my local rose society in the Manawatu and ended up with a list of 91 roses, some of which I thought were not healthy at all but others found they were.

Look into disease tolerant roses

It is also important to note that many of the rose breeders and nurseries are actively selecting their new introductions for excellent disease tolerance. How do they do this? Simple, they grow them in the field for a few years and don’t spray. The ones that get full of disease are removed while those that are healthy are kept for further evaluation.

Sally Holmes, Serendipity and Hamilton Gardens RosesIn the New Zealand Rose Review, here is what members of the New Zealand Rose Society selected as their most healthy roses.

1. Paddy Stephens
2. Iceberg
3. Glorious
4. Sally Holmes
5. Serendipity
6. Hamilton Gardens

These are all good varieties and a worthy starting point if you are looking for something new for your garden that will look good for most of the time.

By Hayden Foulds