A Cold-Climate Gardener Adapts to the Tropics

Farm Manager Elias Rodriques, working in the sunken bed, which is stabilized by vetiver grass and planted with bananas.

Will Raap, Founder, Gardener's Supply

When I first learned about rain gardens and planted one to capture water runoff at our home in Vermont, I never imagined that I'd be planting a second one — 20 years later — at our part-time home in Costa Rica, where my wife has her roots.

Our Vermont rain garden has two parts. The first is a sunken bed planted with moisture-loving plants. Its purpose is to trap water and slowly deliver it to the second part of the garden: adjoining raised beds that are planted with three kinds of raspberries, goji berries, grapes and hardy kiwis. Close plantings and a living mulch of white clover keep out the weeds. A cedar gazebo that I built nearby helps supports the brambles and vines.

Once the fruit harvest is over and winter begins to descend on Vermont, we leave Hardiness Zone 4 for Zone 14, in Guanacaste, Costa Rica. In this tropical paradise, gardeners face huge challenges. The year is split into two seasons: A six-month rainy season from June through November, followed by a dry season that lasts from December through May.

Our Costa Rica garden is actually a 10-acre organic farm and nursery named Finca Mi Tierra. To outsmart the difficult climate (monsoon/desert, heat, wind), we use the Mayan chinampas system of wide raised beds for all-year perennial crops and sunken beds for dry-season crops. As in my Vermont rain garden, the sunken beds capture water and sediment during the rainy months. When the dry season comes, vegetables, fruits, ornamental plants and conservation plants are grown in the sunken beds.

Inspired by my berry garden in Vermont, I have been working with Finca Mi Tierra's farm manager, Elias Rodrigues, to grow an intensivem tropical fruit salad garden. Can we produce delicious organic produce while also developing techniques for maximum output and pest protection? Might what we learn be of use to local landowners interested in improving yields from their farmland, enriching the soil and creating more jobs?

Elias and Lynette, my wife, at Mi Tierra's Tropical Fruit Salad Garden

We planted our first tropical fruit salad garden on a hillside. The contoured rows of pineapple, papaya, bananas, passion fruit vines and perennial peppers are surrounded by erosion-controlling vetiver grass. Though hot peppers don't exactly qualify as tropical fruit, they are popular at market, effective pest deterrents and are the key ingredient in our best-selling chileros hot sauce, which we make and sell under the Mi Tierra brand.

We are pleased with our initial results. We believe we can generate up to $1 per square foot revenue from an intensively planted fruit garden, with crops sold to the local market where organic produce is in demand.

At Mi Tierra, Elias and I are eagerly watching the progress of our fruit garden test. Applying gardening concepts from Vermont, we're adding compost and organic matter to boost soil nutrients, and growing yucca to loosen the heavy clay. These vital organic gardening techniques are being reinvented in a way that suits Costa Rica's extreme weather.

Will plants a trench of spiny piñuela fruit to try to outsmart iguanas.

I have always been interested in producing more food in less space — doing it efficiently and employing ecological solutions, such as healthy soil, compost and drip irrigation. That's one reason why Gardener's Supply has focused on innovations for home composting, water-efficient container gardening, Grow Bags and raised beds.

Our next challenge? Pest control. Our wire mesh iguana fencing should keep out those pesky lizards, but we haven't quite figured out how to stop the howler monkeys. They drop in to help themselves to the bananas and papayas, and eat leaves, fruit and all. I'd rather battle rabbits and groundhogs any day!

Watch a short video of Will in the Mi Tierra Tropical Fruit Salad Garden.