21 Jan 2010

Vegetable Gardening at Latitude 20 Degrees North: Thinking Upside Down


Caymanians have historically tended year-round “grounds” filled with the traditional starchy crops including cassava, yam, sweet potato, pumpkin, and banana/bottler/plantain suckers. Other crops including seasoning pepper, hot pepper, papaya, watermelon and coco-yam were also grown side-by-side. Not-so-traditional crops such as tomatoes, cucumber, peanuts and corn were often times grown at the “best times” by the more adventurous farmer.

Vegetable gardening of the more “non-traditional” crops such as beetroot, turnip and leek in raised beds in backyards or on allotments (starting every spring) was not popular for Caymanians but for some of our new residents who hail from temperate climates, this has been their tradition. Many of these new persons to our Islands are from strong gardening cultures but are used to far different conditions than that found at 20 degrees north.

We can successfully grow many of the same vegetables here as are grown farther North with some notable exceptions being asparagus, globe artichoke and rhubarb. In exchange, we have many more growing options such as okra, aubergine, watermelon, true sweet potato plus the usual suspects including tomato, cucumber, sweet pepper, cabbage, carrot, radish, and beetroot. This is a benefit of Cayman being located smack in between the Tropics and Subtropics – our growing palate is seemingly endless. I enjoy growing peach and strawberry and leek and mizuna as much as I do mango and naseberry and okra and tropical spinach. All are possible here at 20 degrees north.

But there is one simple challenge and often times I get asked the question: why is it that my tomatoes do not bear fruit? In response to this question I will often ask: when do you plant them? Not surprisingly, 9 times out of 10 the response is “I planted them in the spring and summer”.

Thinking upside-down, Rule 1 of 2: Our main vegetable growing season for “non-traditional” crop starts in the autumn and not in the spring or summer. Please note that there are many more reasons for this other than cooler days and nights but that discussion is for another article.

Now on to Rule #2.

Our soils are in the main, very alkaline, shallow, salty (in many cases) and devoid of organic content: classic conditions for composting? Sure, and this is strongly encouraged, particularly in raised bed systems where soils can be modified and developed over a period of 2-4 years to almost perfect growing conditions. Hurricanes also provide an endless supply of green materials which can be readily mulched and used as soil amendments as well.

Compost (either purchased or homemade) and mulch are both natural ways to lower your soil’s ph (most vegetables prefer a ph of around 6.8), increase its organic content; water holding capacity, aeration and its depth. Another naturally occurring mineral, gypsum (which incidentally was the primary basis for the development of the Little Cayman Railroad) will reduce soil saltiness whilst simultaneously reducing soil compaction and providing additional calcium for the soil.

Compost is one of nature’s best mulches and soil amendments and you can use it instead of commercially manufactured fertilisers. Compost also loosens clay soils and helps sandy soils retain water. Adding compost improves soil fertility and stimulates healthy root developments in plants. The organic matter provided in compost provides food for micro-organisms, which keeps the soil in a healthy balanced condition. The 3 main plants nutrients: nitrogen, potassium, and phosphorus will be produced naturally by the feeding of micro-organisms, so few if any soil amendments will need to be added once a healthy balance has been achieved.

Gardening at 20 degrees north, Rule 2 of 2: Spend more time at the beginning feeding the soil and less time treating the plant disease symptoms afterwards.

No comments: