As Perth’s summer heat sets in, our roses face not only soaring temperatures but also the persistent risk of chilli thrip infestation. These tiny, sap-sucking pests thrive in warm, dry conditions and target the soft new growth on roses—especially buds and young leaves. Without intervention, they can quickly cause distorted blooms, bronzed foliage, and stunted growth.
One simple yet highly effective method to deter chilli thrips is watering the tops of your roses—leaves, buds, and petals—in addition to the soil. Regularly hosing down the foliage helps in several ways. First, the direct spray physically dislodges thrips hiding in the buds and shoots, interrupting their feeding and breeding cycle. The moisture also makes the environment less favourable to these pests, which prefer dry, dusty plants.
Secondly, rinsing the foliage helps remove dust and grime that can accumulate on roses during Perth’s hot, dry winds. Clean foliage is better at photosynthesis and transpiration, helping the plant stay strong and healthy. Healthy roses naturally recover faster and are less likely to suffer serious thrip damage.
The best time to water over the top is early in the morning. This allows leaves to dry quickly, reducing the risk of fungal issues while giving plants a refreshing start for the day ahead. A thorough overhead rinse two or three times a week, combined with deep watering at the roots, offers a balanced approach to keeping roses hydrated and pest-free through summer.
By keeping both the plant and its foliage refreshed, you’re not just improving its appearance—you’re creating an environment where chilli thrips are far less likely to thrive.
And remember that this time of the year we have water restrictions so hand watering is definitely something you need to make time for. If you are time poor, please call me and I will set up a care plan for you.
John Kelly