Since you don't have weather particulars to consider, it's difficult to give you advice. Is the rain at night? Mornings? All day? Only certain times of the year? What's the humidity? What are the wind conditions? Soil type? Drainage? Sun duration and time of day? Night temperatures? Day temperatures? Insect problems? Local plant disease issues? All these variables need consideration when discussing growing plants.
I live in an area where wet vs dry years are cyclic. Thus I need to use different growing techniques depending upon the type of year. It's a guessing game that I sometimes get wrong. Some growers here resort to using greenhouses or hoop tunnels to even out the rain issues. Others use temporary rain shelters over row crops.
Raised beds can help and hinder depending upon the growing conditions in the tropics. Lots of factors to take into consideration. In my area, farms even five miles apart often need to use different methods to address rain issues.
There are locations on my island that can grow great watermelons, tomatoes, and sweet corns. Other locations cannot. So to ask, "Can these crops be grown on Big Island Hawaii?" would result in a response of "Maybe, depending upon your conditions and location." There is no set, simple answer.
It's never too late to start! I retired to homestead on the slopes of Mauna Loa, an active volcano. I relate snippets of my endeavor on my blog : www.kaufarmer.blogspot.com
May be you should chose the drier season (in Ecuador Jun-Agoust)....and water only the soil.
Plant as tomatos suffer if they receive too much water over the leaves...but almost al vegetables prefer don't like humid air.
TO: Aviyah Treves
FROM: Eric Koperek = firstname.lastname@example.org SUBJECT: Growing Watermelon in the Wet Tropics
DATE: PM 7:38 Monday 19 September 2016
(1) If Iquitos (Peru) is hot and wet enough for you, the answer is it is best to grow watermelons in the "dry" season. Melon crops do not fare well if they are rained on every day = foliar diseases can wipe out entire crops. Vine crops generally grow best in relatively dry climates.
(2) Melons favor well drained soils with high organic matter contents. Plant on mounds or in raised beds if soils are tight, heavy, or soggy. Excellent soil aeration is essential to keep vine crops healthy. Oxygen deficient soils promote rapid growth and spread of pathogenic organisms that attack plant roots.
(3) For best results, dump 1 bushel = 8 gallons = 32 liters of compost or dried, crumbled cow manure on the soil surface to make a small hill or mound. Set 1 transplant only in the middle of each hill. If you have abundant compost or manure you can make each hill larger. No other fertilizers or soil amendments are necessary. If soil is poor, pile more compost or dried manure. Mulch each vine with any available organic materials. Apply mulch 8 inches deep. Keep adding mulch as it decomposes.
(4) RULE: Never leave the soil bare, not even for a day. Keep the soil covered with mulch or growing plants at all times = 365 days yearly. This is an essential management technique for tropical soils. Vast amounts of Fungi are necessary to maintain the health and fertility of wet, tropical soils. Fungi need moisture and large amounts of organic matter to thrive. Translation: Bare soil = crop failure. Heed this warning.
(5) Insect control will be your biggest problem. Tropical pests can devour your crop in a few days. Protect young plants with floating row covers = cheesecloth or similar fabric supported by hoops. Remove horticultural fabric when plants start to bloom as melons require insect pollination.
(6) The easiest way to grow melons in the jungle is to find a clearing with full sunlight and LOTS OF WEEDS. Search for the weediest field you can find. More weeds = better crops. Clear a small space, about 1 meter diameter, for each melon plant. Leave surrounding weeds standing. The weeds will protect your melons from insect pests. Plant melons as directed above. Space each melon about 12 feet = 4 or more meters apart. You can cut weeds and use these for mulch. Prune or thin weeds as necessary only until melon plants are well established. Once melon vines begin to run, no other care is usually required. The vines climb over the weeds. Vine crops tolerate light shade and grow well in weedy fields. We harvest our best melons from the weediest fields.
(7) If you grow vine crops in a proper garden, scatter the plants around so they are not grouped together. Clusters of the same plant species attract insect pests like a beacon. In tropical jungles you want to plant a polyculture of as many plant species as possible. For best results your garden should contain 40 different species per quarter acre = roughly 100 feet x 100 feet.
For more information about old-fashioned biological agriculture please visit: www.agriculturesolutions.wordpress.com -or- www.worldagriculturesolutions.com -or- send your questions to: Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 USA -- or -- send an e-mail to: Eric Koperek = email@example.com
Aviyah Treves wrote:How to grow Watermelon and other earth fruits (tomatoes, melons, sweet corn) in the wet tropics?
Without knowing anything at all about your growing conditions, I'll give my generic answer to this question...
Talk to the neighbors.
Ask what varieties they are growing and how they are doing it.
Obtain seeds and follow their directions.
Save seeds from any plants that are capable of reproducing, and use them to plant the garden the next year.
Each year, save and replant seeds from plants that are able to successfully reproduce.
If a crop is not typically grown in the area, and you really want to grow it anyway. Obtain many different varieties. Plant them. Let them promiscuously pollinate. If anything at all produces seed, no matter how poorly, save that seed and replant year after year until you find something that thrives. Try different techniques, if necessary, to figure out what the plant needs. I planted runner beans and mixta squash 5 years in a row before I harvested my first seeds from them. Now they grow reliably for me.
My experience growing melons on both the wet and dry tropical conditions (Hawaii) was the vines grew well but every fruit was killed by a fly. You could see right where they'd leave a puncture wound and the fruit would fail to form.