The wet and unpredictable weather this spring has been challenging for local gardeners. Thunderstorms and mud caused garden workdays to be canceled. It seems like the weeds are growing faster than ever while veggies and herbs succumb to fungal diseases. Flooding has destroyed farms and gardens in Waimanalo and East Oahu.

However, we still have some nice weather left before the hot summer comes, and now is the time to get excited and rebuild our gardens.

A little information can be a big help in your gardening endeavors. The University of Hawaii master gardeners are volunteers who help the University of Hawaii at Manoa’s College of Tropical Agriculture and Human Resources (CTAHR) to educate the public about good gardening practices. In addition to service projects and outreach events, our master gardeners also have a help line to answer your questions about garden plants, pests and practices.

With the wet weather, we have been getting lots of calls that we have diagnosed as plant fungal diseases. Tomato plants have been affected by late blight, which causes brown or black lesions on leaves, stems and fruits, and can kill off the whole plant. Powdery mildew, another fungal pathogen, has been thriving on many garden vegetables. It develops a white, powdery film on leaf surfaces.

Many pest and disease problems can be difficult to diagnose, especially if you have never heard of them. A good place to start is with the UH master gardener website. Under “helpful links” on the left side of the page are many good resources and information about plants, pests and more topics.

Another approach is a simple web search. Simply type in the name of the plant, pest, disease or other topic you are interested in, plus the acronym “CTAHR,” to find unbiased, research- based information written by UH faculty for local gardeners and farmers. It’s always best to look for information from local, reliable sources, which may be more relevant due to our unique location.

The recent flooding in East Oahu highlighted the importance of safe gardening practices. Floodwaters are considered unsafe because they may contain fertilizers, pesticides, sewage, animal feces and hazardous chemicals from homes, businesses and roadways. You can do your part by avoiding the use of raw manure, minimizing or eliminating pesticide use, and designing your garden to reduce runoff and erosion from your property.

Vegetables and herbs exposed to floodwaters should be considered contaminated and should not be eaten. For fruit trees and longer-term crops where the edible portion has not been exposed to floodwaters, you may consider the safety of consuming the produce on a case-by-case basis. CTAHR has a great publication for further reading available at ctahr.hawaii.edu.

Finally, what to do with all the weeds that are popping up in your garden? Visit the UH Urban Garden Center in Pearl City on Saturday, for a workshop on smarter ways to control pesky garden weeds. Visit ctahr.hawaii.edu/ougc for more details and to RSVP for the workshop.

You can find master gardeners in person at five farmers markets across Oahu monthly, and on every second Saturday of the month at the Urban Garden Center. For information, visit our website, ctahr.hawaii.edu/UHMG.

Kalani Matsumura is a junior extension agent with the University of Hawaii’s College of Tropical Agriculture and Human Resources and coordinates the University of Hawaii Master Gardener Program on Oahu.