Gardening in midsummer in Kona can be a sweaty task. Unless you have a pool to jump into or can get yourself into the ocean, cooling off after a bout of weeding may not be that easy.
Summer is a good time to think about installing a water feature in your landscape. Adding moving water or a pond to your garden can cool down the area and you. The sound of cascading water while you weed is cooling in itself. The chance to wiggle your toes in a waterfall or wade in a pond can help you cool off without having to leave your garden.
Choosing a water feature depends on your space, taste and budget. You can go all out and create an oasis with waterfalls, a fish pond and water plants or you can simply add a small fountain to cool off a hot spot. You can even create a small stream and a waterfall without a pond if space is limited and you just want the sight and sound of water running over rocks as part of your landscape.
The best way to start planning a water feature is to look at pictures online or in books. One of the best sites for ideas is watergardensideas.info. You can see examples of mini ponds that you can build yourself, as well as larger fish ponds, water fountains, waterfalls, rocky water cascades and even indoor water features.
If you have a shady corner to put in a small fern grotto with a waterfall, you will be delighted with its cooling effect. Full sun locations with a short cascade of water going into a pond or bed of stones can add coolness and relaxing sounds to your landscape. On warm nights, your water feature can become a cool and attractive focal point with a few well-placed lights.
We do have lots of rocks in our Kona soil, which can be used in many ways in fountains, waterfalls and ponds. The addition of water plants in a pond or simply surrounding your water feature with some of your favorite tropical specimens can move your garden from hot to cool. Though the temperature will drop, the appeal will rise as you create a lovely addition to your property.
Gardening with water plants might be a whole new and interesting area to explore. Here, too, you can go from simple to complex. Most water gardeners start with floating varieties that keep pond water clean and provide feeding areas for fish. Water lettuce, water hyacinth and papyrus grow well here. Perhaps too well. They require some vigilance to keep their population under control but they make excellent additions to a compost pile if your pond gets overcrowded. Going beyond the basics, you can add water lilies or even get into lotus cultivation. Don’t forget to consider edible plants like taro and watercress that do well in water. If you live above 2,000 feet where winter nights get cold, you could even try growing your own wasabi in cold running water.
To get some ideas for water features using tropical plants go to pondspools.com or jasonswatergardens.com. Both companies carry plants and pond supplies. Check with them about fish. Adding fish to your pond ensures that mosquitoes cannot breed there. Koi are good fish to consider for an outdoor pond. They are usually trouble free and can forage among your plants for their own food. If conditions are right and they are happy, they will grow quickly and can become quite large. Both size and coloration are considered in pricing koi. A predominance of the gold or red-orange color on the fish increases its value and the larger the fish, the higher the price. Raising koi is another avenue for pond owners to consider and it can become a fun hobby as well as a profitable business. Of course, if you are interested in growing food, you would not want to eat your koi, but you may consider raising tilapia in your pond. These are edible and tasty and can also help keep down mosquito breeding while adding fertilizer for your water plants. An article on raising edible fish in your backyard pond can be found at motherearthnews.com/homesteading-and-livestock/backyard-fish-farming-zmaz06amzwar.aspx.
If you want a cool garden in every way, do consider adding a water feature.
Tropical gardening helpline
Jack asks: My mango tree is loaded and the fruit is almost ripe, but still pretty hard. Lately, I notice that something is eating them. I suspect rats. How can I stop them so that I can enjoy all of my mangoes once they are fully ripe?
Answer: It certainly sounds like you have rats eating your mangoes. Start preventing them from reaching your fruit by isolating your tree. Be sure to eliminate all rat pathways like fences, overhead wires or the branches of other trees. Also be sure that the lower branches of the tree are high off the ground. Prop them up if they have fruit on them. Low-hanging branches give rats access to the tree and provide a protective cover for them. After harvest, prune your tree to be more open in the interior and higher off the ground.
Rat guards on the tree are also a good preventive measure. They can be made from a piece of sheet metal 18 to 24 inches wide and as long as the circumference of the tree plus two inches. Put holes in the sheet metal and use wire to secure the ends of the metal sheet in place.
If your tree isn’t suited to this sort of guard, you can use the sheet metal to create a 2-foot fence around the tree to reduce rodent access. You can also try using both kinds of guards if one doesn’t do the trick.
You can also protect your tree by tying several rat traps around the trunk with the triggers pointing down. If you leave the traps unset for a few nights the rats will get used to them and be more likely to be caught once you do set them. Be sure the traps are tied securely to the trunk before trying to set them. The traps will likely catch rats as they try to get up the tree or at least scare them off. Only set the traps at night to avoid accidentally killing nontarget species.
Good luck with your rat prevention systems. It would be a shame to lose your tasty crop to the rats.
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 on an organic farm in Captain Cook.
Gardening events
Farmers markets
Wednesday: Hooulu Farmers Market, 9 a.m. to 2 p.m. at the Sheraton Kona Resort &Spa at Keauhou Bay
Wednesday: Sunset Farmers Market, 2 p.m. to sunset at the north makai corner of the Kmart parking lot
Saturday: Keauhou Farmers Market, 8 a.m. to noon at Keauhou Shopping Center
Sunday: South Kona Green Market, 9 a.m. to 2 p.m. at Amy B. H. Greenwell Ethnobotanical Garden in Captain Cook
Monday to Saturday: U-Pick greens and produce, 10 a.m. to 4 p.m. Tropical Edibles Nursery in Captain Cook
Plant advice lines
Anytime: konamg@ctahr.hawaii.edu
Thursday: 9 a.m. to noon at UH Cooperative Extension Service in Kainaliu, 322-4892.
Monday, Tuesday and Friday: 9 a.m. to noon at UH CES at Komohana in Hilo, 981-5199 or himga@hawaii.edu.