My roses haven’t performed well this year, which I suspect is due to the hot, dry summer we had. Is there any way I can help the plants so that they do better if we have another similar summer next year? Anna K, Dublin
Although roses enjoy warm, sunny conditions, these hardy shrubby plants also need a humus-rich, fertile, moisture-retentive, deep soil if they’re to flower well. This summer’s hot, dry conditions have tested them, especially plants growing in less-than-ideal growing conditions where their root systems may not have had access to sufficient water and nutrients.
To improve growing conditions, mulch generously around their root systems in spring, using well-rotted manure (Irish suppliers include Cork-based geeup.ie which delivers nationwide) or a commercial mulch such as enrich.ie
Pruning is also important to remove dead, damaged or diseased wood and encourage the production of lots of new, healthy, vigorous, flower-bearing young branches. Exactly how and when you should prune your plants depends on what type of roses they are. A hybrid tea rose, for example, needs a different pruning regimen to a climbing rose or a rambler. For detailed advice on this, check out the website of the RHS at rhs.org.uk
Working a slow-release organic fertiliser into the soil in spring will also help to supply important plant nutrients, as will regular liquid feeding during the flowering period. Deadheading is also important, as this prevents the plants from turning their energies to producing seed and instead encourages them to produce more flowers.
Also bear in mind that most roses like to have a little space around their root systems rather than be squeezed in tight with other plants. If, for example, perennials or other shrubs have been allowed to gradually encroach upon your roses, then consider gently cutting these back.
Lastly, no plant lives forever. While roses are more long-lived than most – they can typically live for 10-20 years, while climbing roses in particular can live for up to a century – plants naturally and gradually lose vigour over time and will eventually succumb to disease and old age. While you can slow this process down through careful husbandry as described above, as well as by collecting and disposing of any diseased material in early spring, you can’t prevent it.
If your plants are old, then they may be reaching the end of their natural life cycle. If this is the case, then consider the possibility of replacing them with young, vigorous roses, ideally choosing a vigorous, productive, floriferous variety known for having good disease resistance. But just bear in mind that a disease known as rose sickness or rose replant disease can sometimes cause these new plantings to struggle for reasons that aren’t yet fully understood.