An expert says gardeners must take action now to protect roses from sap-sucking insects and fungal diseases. Warm spring temperatures so far mean blackfly and greenfly will be particularly prevalent this season, according to Hayden Salt of Jacksons Nurseries.He warned rose owners will need to start spraying now to protect against tiny aphids and diseases such as black spot to ensure rose blooms are stunning by summer.

Hayden said: “Roses are quite prone to pests and diseases so it’s really important people take steps to protect them. But the good news is with proper care and attention they can continue to bloom well year after year.

“The warm temperatures we’ve experienced so far this spring mean blackfly and greenfly are expected to be around in large numbers.”

Aphids, of which there are around 500 species in the UK, are notorious for their rapid reproduction and can form dense colonies, weakening plants and extracting vital nutrients.

This can result in stunted growth, deformed leaves and can even kill plants. Hayden, who has 25 years’ experience in horticulture, said: “Aphids are usually quite obvious as you can see them on the plant, as well as the sticky substance they secrete called honeydew.

“I would recommend using a three-in-one spray every fortnight to tackle this issue, as well as that of fungal diseases.

“Diseases such as black spot, powdery mildew and rose rust are very common and can mean infected leaves drop off. In the most serious cases it can kill the plant entirely.

“Sprays can be used on a preventative basis so you don’t need to wait for signs of disease or aphid problems to take action.”

As well as taking steps to keep your roses healthy and happy, it’s also worth applying a slow-release, balanced feed this time of year to ensure the plant is properly nourished.

Hayden said: “A rose feed will provide key nutrients that will support healthy root growth and encourage abundant flowering. 

“Slow-release versions will allow the feed to be absorbed through the roots over time.

“In June I would recommend switching to a liquid feed that’s high in potassium, such as tomato or a liquid-based seaweed feed.

“Roses expend a lot of energy during the flowering period. Applying a liquid feed every two weeks whilst they’re flowering helps restore and maintain their energy levels, resulting in continued healthy bud and flower growth throughout the flowering season.”