The Flora of Tropical East Africa provides descriptions of over 12,000 wild plant species. Two-thirds of the flowering plants are dependent on wild pollinators, and many of these plants have coevolved, over millions of years, with the wild pollinators that pollinate them.
Most pollinators are wild insects. For plants and wild insects to thrive, areas of natural habitat are critical, and perhaps the single most important prerequisite.
Areas of natural habitat near or within farms provide two essential things to support pollinators: sources of food (nectar, pollen, and host plants) for pollinators and their larvae, and equally important, secure nesting sites.
Farmers, and gardeners can encourage wild insects, and other pollinators by maintaining, and creating spaces of natural habitat. Natural habitat can include:
• a forest edge rich in wildflowers
• roadside verges, which are not consistently shorn
• a hedgerow composed of different flowering plants
• wildflowers conserved, or planted within a field.
Insects of five different Orders provide us with pollination services for our crops: Hymenoptera (ants, bees and wasps), Diptera (true flies), Lepidoptera (butterflies and moths), Coleoptera (beetles), and Thysanoptera (thrips). A few bats and birds also provide pollination services for a smaller number of plants. Bees, both solitary and social species, pollinate the majority of our crops and fodder, being entirely dependent on pollen and nectar from flowers for their survival.
Some bees, like honeybees and stingless bees convert nectar into stores of honey. Most bees, especially the solitary bees, collect pollen, and store this as food for their larvae. Many bees only forage a short distance from where they build their nests, so endeavour to have a diversity of wildflowers close to their nesting sites.
The more diversity of plants that are present and flowering across seasons, the better the conditions for bees. The types of plants in an area will depend on the habitat. In seasonal areas (which is most of Kenya), both annual and perennial plants are important. Wildflowers that grow at the edges of forests or in woodland areas tend to flower for longer periods of time.
Ocimum, Justicia, Leucas, Bidens, Indigofera, Crotolaria, Cleome, Commicarpus, Barleria, Aspilia, Crassocephalum, Emilia, Gutenbergia, and Vernonia spp. are some of the wildflowers that are particularly attractive to bees.