mind the hive: Bees do a good job at pollinating flowers. Photos: Normita Thongtham
Following the column on pollination two weeks ago, regular reader Bob Neylon wrote from Pattaya to say that he had a small vegetable garden as well as many fruit trees and shrubs. A couple of years ago, he bought a hive of the stingless variety of bees from the local agriculture department to pollinate his plants. “They have been OK but no real big deal,” he wrote.
Mr Neylon expressed surprise that bats are a good pollinator of dragon fruit. “We do have some plants growing for about eight years that are good producers, and we have a lot of bats as well. About eight months ago we planted some passiflora on a trellis we had for grapes that didn’t work out too well. About two months ago it started flowering but fairly sparse.
“I did a bit of research and found that the best pollinators of passiflora are carpenter bees. I have been hand pollinating the flowers for the past couple of months and right now have about 18 fruit as well as more than three dozen I have pollinated in the past few days. I noticed a large bumble bee around the plants recently and he seemed to be doing his job. Hopefully this will work out for me as the stingless bees are too small and the pollen too sticky.”
Mr Neylon wanted to know whether there were carpenter bees in Thailand. “My concern is if the passiflora are not in flower, will the bees hang around or will they also visit other veggies, etc?” he asked. “If this would be the case it may help on other crops that need hand pollinating as well, such as watermelons, other melons, some types of tomatoes, and the long cucumber. That would be a real bonus.
“The last question is about watermelons and other melon types. Will they grow well during the rainy season? I live in Huay Yai about 2km from the ocean. Normal rains but pretty high humidity in the late afternoon to early evening. Veggies not to plant in rainy season?”
First, the dragon fruit. Some years ago, Mr Neylon wrote to say that he planted both the white-flesh (Hylocereus undatus) and the red-flesh (Hylocereus polyrhizus) varieties of dragon fruit. While the white-flesh variety bore fruit without any problem, he had to hand-pollinate the red-flesh variety so in the end he discarded it.
During a visit to our farm, we arrived around 9pm and passed by dragon fruit festooned along our neighbour’s fence. They were in full bloom and the flowers seemed to be glowing in the moonlit night. That’s when I realised that they were pollinated by bats, that’s why they opened at night.
Handle with care: Without bees, only hand pollination will help these passiflora flowers turn to fruit.
Dragon fruit flowers have all the characteristics of a bat flower: they are coloured white with a strong scent to attract pollinators, and with a pendulous stalk so that bats could pollinate them without being hindered by foliage. Early the following morning, I went to see the flowers and there were bees and other insects on them, too. I am thus certain that dragon fruit flowers are pollinated by both bats and insects. As the flowers of both the white-flesh and the red-flesh varieties look almost the same, both should be visited by the same pollinators.
I used to have a Passiflora edulis, or passionfruit, vine climbing along my fence in Bangkok but it had only flowers, probably because there were no pollinators. I have no doubt, however, that had the plant lived for another year or two, insect pollinators would eventually discover it. Carpenter bees are the best pollinators of passiflora but bumble bees and other insects should be able to do the job as well. My friend Phen in Phetchabun just leaves her passiflora vines alone, yet they give her a bountiful supply of passionfruit juice every year.
Bees are intelligent creatures; they seem to know where to find flowers in bloom. Therefore, Mr Neylon does not have to worry that when his passiflora is not in bloom they will go away and never return. They will go away to search for other flowers but I am sure they will come back when his plants are blooming again.
Last but not least, leafy vegetables can be planted in the rainy season as long as the soil is well drained. It will help if they are planted in raised plots for better drainage. Melons, however, should be planted in time for the fruit to develop in the summer, otherwise it will not be sweet. One thing to remember: hand pollination helps ensure that the flowers get pollinated, but honeybees, bumble bees, carpenter bees and the many other kinds of bees do a very good job of pollinating flowers if you give them a chance. Do not spray your plants with insecticides when they are in bloom.
Meanwhile, beekeeper Oleg Kulikov wrote from Sa Kaeo to say that he has been engaged in apiary for the past three years. He has even invented a special beehive after finding that the Western-style structure could not be efficiently used for local honey bees. His problem? He lives in the wrong place: Sa Kaeo province does not have many orchards and flowering plants. He thinks that growing more fruit trees, sunflower and nuts would improve the life of Thai agriculturists, but this would need government support.
“With more flowers in Thailand, a need for bees as pollinators and for my beehives would come,” he wrote. “The beehive I have invented is adapted to the tropical climate and its production cost is very low as I use local materials to build it.”
Mr Kulikov is thinking of producing more beehives, in the hope that there will be a market for them in the near future or in other places, in Thailand and other Asian countries. He also wants to patent his design, and is looking for any person or organisation who could help him go about it, with a promise of sharing with them future royalties. Any takers?
Not too wet: Vegetables can be planted in the rainy season as long as the soil is well drained.
This source first appeared on Bangkok Post Lifestyle.