The recent wet weather and cool nights have unfortunately created the perfect growing environment for unwanted garden guests: mildew and fungus. Sam Bradford of has heard many stories from customers.
“It seems like overnight we’re getting reports of powdery mildew (a type of mildew), and many customers are rushing in to find out how to treat it.” says Bradford.
Unfortunately mildew and other funguses are difficult to treat after they have infected plants. The only way to treat for fungus is to do is through prophylactics.
Some fungi can be so potent, that it can wipe out many crops. Many local residents may recall the tomato blight of 2010 and that it wiped out entire crops at local farms. The only farms that were able to produce a full crop of tomatoes were the ones that treated in advance of the blight. Once disease infects a plant, its survivorship rate is close to zero, plus spores are carried easily on the wind, and within hours can start to infect other plants. Wilson Farm’s Jim Wilson indicated that tomato blight has already been detected in 5 northeast states, so it looks like there is an elevated risk of tomato blight and other fungus issues this summer.
While not all funguses are as detrimental to plants as blight, now is the right time to protect favorite shrubs, annuals, perennials, vegetables and fruits. The most common current fungus issue is powdery mildew which appears as white, powdery spots that most commonly appear on one or both sides of the leave, the shoots and occasionally on flowers. Typically, plants infected with powdery mildew will exhibit one or more of the telltale damage: yellowing of leaves, twisting and buckling, and occasionally brownish spots.
Prevention is a gardener's best friend and there is a primary method to limit damage by such mildews/fungi. First, start by strategically spacing plants apart so it receives adequate air circulation. Fungicides are also helpful in the prevention, and can also help limit damage once an infection has started. Many natural non-toxic options exist such as horticultural oils, sulfur based anti-fungicides and even biological fungicides work well and are easily available. The ideal option depends on many vegetation and symptom factors, so it’s advisable to consult a knowledgeable garden shop for the best advice.
If a plant is displaying unnatural color or textures and its ailment is uncertain, bring a clipping in a Ziploc bag to the local garden shop for a more thorough evaluation.
Now that the most of the planting has been completed in the garden, it is important to monitor the health of the plants throughout the season. It would be a shame for those months of preparation and effort to be wasted on preventable and unsolicited garden tourists. Anticipation is the key to maintaining a successful garden and a scrutinized eye is all that is needed to a victorious harvest.
Information for this article was contributed by Wilson Farm, 10 Pleasant St., Lexington.