Donna asks: With all the rain lately, weeds are going gang busters in my garden. Any tips for dealing with them without using chemicals?
Donna asks: With all the rain lately, weeds are going gang busters in my garden. Any tips for dealing with them without using chemicals?
Tropical Gardener Answer: Lots of choices exist for weed control without using chemical herbicides. I’ll describe a few here, but you might want to catch Melanie Bondera’s talk, “Alternatives to Herbicides” Saturday at the Kailua-Kona Public Library. She’s been farming organically for more than 15 years and has tested lots of techniques. Catch her talk starting at 10 a.m. if you can.
At this point, you should probably try to get rid of as many weeds as possible before employing some of the preventive measures explained here. If pulling weeds by hand is not a pleasant meditative practice, even if you take a small stool to save your back, try using a hoe or hula hoe to get large areas of young weeds up quickly. Mostly, you want to remove them before they go to seed to prevent sowing a new generation.
Weed burners will effectively burn down the tops of weeds, but be careful to avoid starting a fire in dry brush. If weeds are young, household vinegar can burn them down, also. High concentrations of acetic acid or mixing it with salt is not recommended as these can have deleterious effects on surrounding plants.
Goats or geese might be an option for large scale weed control as well, but you’ll need to protect non weedy species from them. They can be voracious eaters which can translate into lots of feces for soil enrichment.
Once you have removed most of the weeds you have now you can prevent new weed growth in several ways. Applying three to four inches of mulch in your garden will definitely slow down weed growth. It will also make weeds easier to pull and the mulch will break down, enriching your soil. Installing plants to serve as ground covers can provide a living mulch to crowd out weeds. Planting trees that shade weedy areas will discourage the weeds but may also hamper the growth of your sun loving plants if they get shaded.
Covering the soil with cardboard or a thick layer of newspaper can also discourage weeds. Be sure to put rocks in place to prevent the paper from blowing away.
Sometimes the best way to deal with something unpleasant is to find a good use for it. Many weeds have medicinal uses, can provide clues to soil toxins or are edible. Getting to know their identity and researching potential benefits might help you come to terms with their presence while you figure out the best way to deal with them on your property.
If you want to learn about other options, check out the talk at the library on Saturday.
Email plant questions to konamg@ctahr.hawaii.edu for answers by Certified Master Gardeners. Some questions will be chosen for inclusion in this column.
Diana Duff is a plant adviser, educator and consultant living in a dryland forest north of Kailua-Kona.
Gardening Events
Today: “35th Annual Kona Daifukuji Orchid Club show and sale” from 8 a.m. to 2 p.m. at the Daifukuji Soto Mission Hall on Highway 11 at mile marker 114, just north of Kainaliu. The free event offers educational displays of many orchid species. A question and answer booth with expert advice on orchid care will also be onsite. A sale of high-quality orchid species and hybrids is also part of the event. Club members can offer membership information and will be selling home-baked goods and drinks. For information on the Orchid Club, check out their Facebook page at www.facebook.com/orchidsinparadise.
Saturday: “Work Day at Amy Greenwell Garden” from 9 a.m. to 12:30 p.m. Meet at the Garden Visitor Center across from the Manago Hotel in Captain Cook. Volunteers will be able to help with garden maintenance and are invited to bring a brown bag lunch. Water and snacks provided. Call Peter at 323-3318 for more information
Farmer Direct Markets
Wednesday: “Sunset Farmers Market” 2 to 6 p.m. in the HPM parking lot at 74-5511 Luhia Street in Kailua-Kona (across from Target)
Wednesday &Friday: “Hooulu Farmers Market” 9 a.m. to 2 p.m. at Sheraton Kona Resort &Spa at Keauhou Bay
Friday: “Pure Kona Market” 9 a.m. to 5 p.m. at Amy Greenwell Garden in Captain Cook
Saturday: “Keauhou Farmers Market” 8 a.m. to noon at Keauhou Shopping Center
“Kamuela Farmer’s Market” from 7 a.m. to noon at Pukalani Stables
Sunday: “Pure Kona Green Market” 9 a.m. – 2 p.m. at Amy Greenwell Garden in Captain Cook
Tuesday–Saturday: “U-Pick greens and produce” 10 a.m. to 4 p.m. Tropical Edibles Nursery, Captain Cook.
Plant Advice Lines
Anytime: konamg@ctahr.hawaii.edu Tuesdays &Thursdays: 9 a.m. to noon at UH-CES in Kainaliu – 322-4892
Mon., Tues. &Fri: 9 a.m. to noon at UH CES at Komohana in Hilo 981-5199 or himga@hawaii.edu