If you have been paying attention you know that our pollinators — bees, butterflies and other insects — are in decline. Why should we be concerned? Because butterflies, bees and other animals that transfer pollen between flowering plants are responsible for the reproduction of 90 percent of all plants on earth! Honey bees are some of the primary pollinators in North America contributing to the production of 90 commercial crops which contribute $24 billion to the U.S. economy. In its very simplest terms, flowers don’t produce fruit or seeds unless they are pollinated.
Some of our urban practices that contribute to the decline of our pollinator populations are the reduction of nesting habitat such as leaf litter or dead wood; our intolerance for ‘weeds’ (dandelions are the first nectar source for bees in the spring); loss of sites for foraging; an overabundance of non-nutritious plants; and over use, and incorrect and unnecessary use of pesticides.
So what can we do to help restore our pollinator population? We can use fewer pesticides and plant a wide variety of nectar rich flowers that provide continual bloom from April through October.
At lot has been said about planting native perennials that provide nectar and pollen for bees and other pollinators. But most perennials only bloom for two or three weeks and so we try to plant a variety of them that bloom at various times. But trials in 2015-2017 at the U of M have discovered a number of annual plants that are very attractive to pollinators.
At the trial gardens in St. Paul and Morris, a variety of annuals were planted and by careful observation of insect activity some patterns and specific varieties were identified. In general flowers that had patterned or multilayers petals were more attractive than single layered petals. More pollinators were attracted to a landscape that had varying heights, sizes, forms and bloom times. Specific annual varieties that were observed to be most attractive were: Sunflower: Lemon Queen and Music Box Mix (dwarf variety); Marigold: Bambino; Rudbeckia: Orange Fudge; Zinnia: Envy , Pop Art- Red and White, Old Mexico; Salvia: Summer Jewel Red; Hyssop: Heather Queen; and Melampodium: Showstar.
Horticulturists from the U will continue the trials this year at farms in St. Paul and Morris and they are hoping to add the new Bell Museum site as an additional trial space. Hopefully by next year they will have some more plants to recommend for pollinators next year.
Fortunately, our sudden shift from winter to summer means it is time to plant annuals. If you think your gardens are full take a stroll around your yard and see if there aren’t a few open spaces where you could tuck in a few annuals.
If you started some seeds indoors or purchased seedlings from a garden center you should ‘harden’ them off before planting them. Move these plants outdoors to a protected space and give them some direct sunlight for a few hours, increasing the amount of sunlight every day. Be sure to take them inside if below freezing temperatures are predicted. After a week or two they should be ready to plant. Once you have identified a spot be sure to prepare the soil by turning it over and adding some compost. To reduce transplant shock, plant in the early morning or late afternoon. You may want to stake tall plants until they develop stronger stems. Apply a starter fertilizer after planting. (Just a 1/2 strength solution of your regular fertilizer will do.)
Check on your plants every day or so and water when the top layer of soil is dry; water early in the day to reduce evaporation and leaf burn, and water where it is needed at the soil level. Consider using a watering wand or soaker hose so that you can water at ground level and avoid wetting the foliage. Lastly, if you want to keep your annuals blooming throughout the growing season practice deadheading; that is removing spent flowers as they fade. This will encourage the plant to produce more flowers.
Have fun adding to your pollinator friendly landscape with annuals.