UC Master Gardener Debbie D. shared advice on caring for roses in April, outlining fertilizing, deadheading, pest management, and fungal disease prevention in a column published on Apr. 1.
The guidance is intended to help gardeners maintain healthy roses through spring’s challenges, such as pests and changing weather conditions. This information supports the broader mission of University of California Agriculture and Natural Resources (UC ANR), which delivers science-based education to communities across the state according to its official website.
Debbie D. said that after the first bloom cycle, gardeners should deadhead and fertilize their roses to encourage a second bloom about six weeks later. She described proper deadheading techniques: “When the flower is ‘finished’ blooming, pinch or cut it off at the base of the flower where it joins the stem.” She added that when all blooms on a stem are finished, gardeners should cut just above the first leaf with five leaflets and trim tall stems for an even shape.
On managing pests, she recommended checking both sides of leaves for aphids and using water sprays instead of pesticides if ladybugs are present because they eat aphids. For spider mites—which can quickly damage plants—she advised daily blasts from a hose or horticultural oil under certain weather conditions. Hoplia beetles may also appear this time of year; she suggested removing them by hand or with soapy water but noted mixed results: “So, squishing them is my preferred method.”
Debbie D. also discussed common fungal issues like botrytis, black spot, powdery mildew, and downy mildew. She does not use fungicides but instead removes affected plant parts and maintains good air circulation around bushes: “I make sure there are no dead rose leaves under my rose bushes as they can harbor fungal diseases.” To prevent problems like black spot or mildew, she recommends morning watering only with sprinklers and keeping areas beneath bushes clear.
The column briefly introduced different classes of roses—including species roses, Old Garden Roses (pre-1867), Modern Roses (post-1867), European fragrant varieties like Damask roses that bloom once per season, and China roses known for repeat blooming—and promised more details in future columns.
According to the official website, UC ANR secures funding through public contributions to support its programs while promoting sustainable practices that strengthen resilient ecosystems and economic vitality throughout California. The organization utilizes nine research centers representing diverse ecosystems across the state according to its official website. UC ANR has gained recognition for trusted services linking research directly to community needs according to its official website.
As part of the University of California system managing Cooperative Extension services according to its official website, UC ANR conducts over 33,800 educational events annually with more than 18,400 volunteers engaged in various initiatives according to its official website. It operates programs in all 58 counties statewide through workshops and partnerships supporting environmental stewardship and community development while mobilizing volunteers statewide according to its official website.
