Monday, September 1, 2008

Vegetable Growing Research in tropical Western Belize


by Ray Auxillou, April 2008

( funded by volunteers of the Belize Development Trust NGO )

Research staff: Ray Auxillou
Contributing Volunteers: Brian Keating, Sharon Auxillou Urscheller, Wendy Auxillou, Bob Brotherton, Lynn Jackson, Gale, Taiwanese Vegetable Mission of Government’s Central Farm, Manuel Trujillo-Central Farm research head.


Vegetable research in tropical Belize has identified a number of parameters in vegetable growing; from temperature, soil adaptation requirements, seasons, nutrient mixing applications, germination problems and alternative methods, better seed varieties, compost tea making and applications, soil ph testing, best shading and roofing and many other variables found in the FOURTH EDITION of the Belizean Vegetable Farmers Bible. Available for reference at the two public libraries in the Cayo, Western Twin Towns of Belize. A half dozen copies are on sale at AGRO PRO feed store in Santa Elena Town at $70 Bz each.

As of March, 2008 we have now identified a number of necessary knowledge items from two years of past experiments, to effect a new project for the first PILOT PROJECT of a tomato shaded greenhouse. This project is intended to lead into a commercial 1000 plant shaded greenhouse. From there you could go to a 10,000 plant shaded greenhouse with not much trouble.

The MILPA farmer grows in soil to two rainy season restrictions a year. The commercial shaded greenhouse system has a steady production on a weekly planting, year round basis. Vegetable production is continuous in a shaded greenhouse. Through the controlled application of water and nutrient feeds constantly producing harvests of crops are experienced.

The first shaded green house measuring 6 ft X 14 ft, growing 60 plants at one time was successful, using the most basic, hand fed, hydroponic system. This first shaded greenhouse continues to produce vegetable salad crops for the “Falconview Tourist Backpackers Adventure Hostel”. Harvesting is done twice weekly. Planting about once a week.

The second PILOT PROJECT intended to be a lead experiment into an eventual commercial sized operation shaded greenhouse, is intended to test the problems and varieties available for commercial production of tomatoes on a year round production basis, using the same basic hand fed method as the first shaded greenhouse project. The size is 13 ft x 19ft and it holds 200 tomato vine plants.

Many varieties of tomatoes are being grown and tested. The best so far, has been the 2 ¼ inch x 3 ¼ inch, ( 6 oz) POLINA Israeli hybrid, available from Agro Jiron feed store, in San Ignacio Town. New varieties are now being grown, and hoped to be larger and better tomatoes. The experiments are geared to attempts, to produce a 14 oz tomato, for commercial production on a year round basis.

The first shaded greenhouse experiment identified so far, as the best leaf lettuce varieties; the ICE lettuce, the Chinese Lettuce of Pok Choi and Jon Choi and Tropical Emperor hybrid at this time. Many varieties of lettuce were tested. More than a dozen.

Seeds brought into Belize do not necessarily work well under local tropical environmental conditions. The beautiful Mexican BALL HEAD lettuce seeds for instance, were a failure in Belize.

What has been found is that soil has to be loose, very easily drained and so coarse. Most of the time you have to mix it up yourself. In a greenhouse project we use either plastic grow bags of different sizes, plastic buckets and chlorax pots. Cost and availability being the deciding factors.
a) In the Tomato Shaded Greenhouse project, we have identified humus, the very thin 1 inch layer of top soil available in lowland wild jungle as the best contained supporting material for vegetables in bags or pots. We had hoped to get coconut fiber from Central Farm, but I was informed in the last visit, the project was too labor intensive. They don’t have the time.
b) The soil is prepared by soaking the bottom third of the soil in compost tea, to make available micro nutrients.
c) The top third of a container of this humus is mixed with GYPSUM, a calcium additive that helps vegetable plants to get started and develop strong root growth. DOLOMITE LIME would be better, but we cannot get the producer, Belize Minerals of Punta Gorda, to ship it to the Cayo West area, from Southern Belize. Dolomite Lime is different from GYPSUM because it includes Magnesium Sulfate and most vegetables need 2% of this mineral added for good production. Gypsum is available for sale locally and is reputed to release the nutrients from local black clay.
d) We have experimented with different containers and found that the large plastic grow bags from AGRO PRO, Santa Elena Town work the best. They hold about six pounds of soil. They have different sizes we tried. No other local feed stores carry suitable grow bags. We tried two tomato plants, planted into a five gallon plastic bucket, but it is difficult to stop the soil from compacting, reducing aeration to the roots. Our best choice is a large black plastic grow bag, which have many holes in the sides and bottom for drainage.
e) Currently we are harvesting POLINA tomatoes. We have just transplanted a number of large tomato varieties, such as BEEFMASTER, BURGER, CREOLE, using whatever is available through the generosity of volunteers in the USA and the UK. We prefer HEIRLOOM varieties, which are adaptable and reproducible, from our own seeds. The HYBRID varieties are one crop types and revert back to the genes of one or the other of the two parents from their seeds.
f) We learned a lot. Originally our tomato vine plantings ( indeterminate types ) were based on 60 plants. It quickly became clear, that doing continuous shaded greenhouse production, that if we widened our bench on which the grow bags sit, we could double and triple our number of plants in the same space. This is due to the fact that vines are continuously running, growing out. The leaves required at the top of the vine, after pruning, for photo synthesis move up steadily. This allows a next set of bagged tomato plants to be grown next to them, as the leaves of the next plant are at a different height and can catch the sunlight required. We are currently potting and transplanting more plants to see how many we can get into the space.
g) QUESTIONS: The experiment in this pilot project raises some questions requiring more testing.
h) We want to know how many tomatoes we can expect from a vine before it will top out and stop growing? We are guessing at four?
i) We need to go to a drip feeding system to each grow bag. We did collect a courtesy sample from the Taiwanese Vegetable Mission of an old drip feeding system they had chopped up with their roto-tiller as they changed to a different watering system in soil row based crops. We require about 200 plastic stakes as drip feeders, the connecting .050 black plastic branch feeder hose and the plastic T fitting, to plug into an overhead ½ inch black supply hose for water and nutrient by gravity feed. The feeder lines slide over the drip stakes, that are pushed into the soil of the grow bag. Research from Guatemala; producers of irrigation supplies enquiries, by e-mail, receive no replies. These people are very rude. The phone system from Belize by BTL to Guatemala is prohibitively expensive. The difficulties of ordering from hydroponic suppliers in the USA, are expensive because the orders are too big to come by ordinary mail, yet too small to be shipped down by ship and run through customs with the additional costs of having to go to the coast and waste a day or two, plus the cost of freight forwarders and customs brokers. The shipment is too small for the mandatory costs. There are no importers bringing in bulk irrigation supplies yet, though there is a modest demand at this time locally, which will grow. We need a roll ( $42 usa ) of the .050 black feeder hose and matching 200 plastic drip feeding stakes, plus T fitting to insert into the overhead water line, from the hydroponics supplier ( HYDRO GARDENS ) in Colorado Springs. We would also need the slightly larger black plastic hose ( ½ inch ) for running the overhead gravity feed water system. This is not too much, as we probably only need a 150 feet of the latter, but 600 feet of the thinner spaghetti type feeder hose for the drip feeder stakes. At the moment the overhead drip gravity feeding system is of necessity on hold. Though hand applications of water and nutrient is labor intensive as our experiments grow bigger with many more plants. The reason for black hose, is algae buildup in clear hoses when sunlight hits the lines.
j) WHAT WE HAVE LEARNED! We have learned that shaded greenhouse operations can be operated successfully on a continuous production basis. There is one catch to this and that is there are two seasons for shaded greenhouse vegetables. Unlike the soil based MILPA farmer whose two seasons are based on the seasonal two rains. The shaded greenhouse operation seasons are based on TEMPERATURE of the outside night time air. The FOURTH EDITION of the Belizean Vegetable Farmers Bible, published in January, 2008 gives a list of vegetables that are temperature sensitive. These group vegetables, into those that are productive during the colder months of the year and those that are productive during the hotter summer months of the year. See the Fourth Edition of the BIBLE on vegetable growing for a list of which vegetables work best at which season.
k) PLANTINGS: Vegetables that require colder night time temperatures can start to be planted in September, weekly through February. Those that are hotter temperature summer vegetables can be planted in February and grown through to approximately September. For example: Tomatoes are a colder night time temperature requiring crop. Sweet Bell Peppers and most peppers are summer crops and go dormant during cold months. Some vegetables can be grown year round. Lettuce can for example!
l) GERMINATION PROBLEMS: If you can get the seeds to germinate, then you can grow the vegetable. Though fruit performance will increase if it is in the right season. Winter vegetable seeds do not germinate well from April through August.
m) We are ready to go commercial almost, with lettuce shaded greenhouses and are waiting to solve vacuum bag packing experiments. We plan to do an experiment on this with ebb and flow methods, growing lettuce, using a pump and two reservoirs. We are waiting on the needed equipment and there is no hurry due to lack of land. At the moment we also lack the land for expansion. So, that particular lettuce producing, commercial shaded greenhouse is currently on hold. We do have a bid in though, for a nearby piece of land, which is currently in probate.
n) I think we are going to be ready to go commercial size on the tomato production with a 1000 plants, once we settle on the best variety to grow and if we can successfully acquire some land to build on. These tomato experiments are ongoing, for the next three months. Decision time is probably going to be around June? We also lack the drip feeder stakes, the hoses and fittings.
o) We are currently collecting SWEET BELL PEPPER seed varieties and will start very small scale tests in growing in pots, within the next few weeks. We are only interested in large 4 inch sweet bell pepper seeds. The commercial shaded greenhouse requirements would face the same problems of lack of pumps, reservoirs, drip feeding stakes and irrigation hoses. Which we cannot seem to find to buy locally.



Abhishek said...

We are exporters of dolomite lime in india if required we can export it for vegetable growing.

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