Impatiens Downy Mildew

Impatiens Downy Mildew

You may be aware of recent problems with common Busy Lizzies (Impatiens walleriana) caused by Impatiens Downy Mildew.

Impatiens Downy Mildew is an airborne fungus, which causes yellowing of the leaves and a white powdery-looking, fungal growth on the underside of the leaves. This is followed by loss of the leaves and flowers leaving just a skeleton of the plant’s stems. Plants will eventually die.

The disease spores can remain in the soil from one season until the

next and can spread rapidly in wet summer conditions. There is currently no chemical control available to the amateur market. We recommend that any infected plants are disposed of, burnt or buried deeper than 50cm (20in). Affected areas should be rested from growing Impatiens walleriana for at least a year to avoid recontamination. Where infected plants have been grown in containers, replace the compost and wash and use a garden disinfectant, as directed by the manufacturer, to cleanse the container if you intend to grow Impatiens in it again the following year.

Although other plant suppliers have removed Impatiens walleriana from their range completely, as many of our customers have reported that they have successfully grown Impatiens walleriana over the past two seasons, we have decided to continue to offer Impatiens walleriana to our customers.

Impatiens walleriana supplied by us will have received applications of commercially available fungicides to protect them during the production process, however we cannot guarantee that they will remain disease free once planted out. If you have had problems in previous years, we would not recommend attempting to grow them again in the same area for at least two years.

Impatiens Downy Mildew is specific to seed grown Impatiens walleriana and does not spread to and will not affect other bedding plants. New Guinea types (Impatiens hawkerii) are not affected.

Brookside Nursery