Utah Sweetvetch

We seem to be having an early start to our blooming season in the gardens this year. An unseasonably warm April brought out the flowers 2–3 weeks earlier than normal. One of the earliest to bloom was Utah Sweetvetch (Hedysarum boreale), a perennial that is native to the western U.S.  This wonderful legume has dense clusters of pink flowers at the tops of short stems, and bumble bees are often seen feeding from them. It makes a colorful statement when planted in large patches, and it looks especially attractive when paired with Blue Flax (Linum perenne) or Sticky Purple Geranium (Geranium viscosissimum).

Sticky Purple Geranium

Blue Flax has sky-blue flowers, and plants bloom for a long time.  It is tolerant of a wide variety of conditions and is very reliable in the garden, along roadsides and in meadow plantings.  Sticky Purple Geranium is a native wildflower with white to purple, single flowers that look nothing like our cultivated geranium that is sold as a bedding plant and used in hanging baskets. 

Another great spring bloomer that looks terrific with Blue Flax is Siberian Wallflower (Cheiranthus allionii).  It creates a bright orange carpet of color whenever it’s in full bloom.  Siberian Wallflower has fragrant flowers that attract bees and butterflies. 

Blue Flax and Siberian Wallflower

Purple Rockcress (Aubrieta deltoidea) and White Rockcress (Arabis alpina), are lovely groundcovers or rock garden plants that are very low growing and have masses of flowers that provide exceptional color:

Purple Rockcress

White Rockcress

Scarlet Globemallow

Scarlet Globemallow, also known as Cowboy’s Delight, bloomed very early this spring.  It is a perennial that is found throughout the Great Plains, from Manitoba south to Texas and Arizona.  It prefers well-draining soils and sunny locations.   It’s distinctive orange flowers make it easy to identify in the wild.

Basket-of-Gold

Basket-of-Gold (Aurinia saxatilis), as its name implies, has bright yellow flowers.  The low-growing mounds of vivid yellow flowers add a cheery accent to spring gardens and always remind me that spring is truly here.  It is excellent for the front of borders or in rock gardens, and it is a good addition to pollinator gardens because it feeds small bees in  early spring.

Narrow-Leaved Beardtongue

Narrow-Leaved Beardtongue (Penstemon angustifolius) is a native of the Great Plains, from South Dakota and Montana, south to Colorado and New Mexico.  The tips of the stems tend to arch initially and then become more erect as they mature and start to bloom.    The flowers are pink-violet to light blue in color, and the leaves are light green with a whitish cast.

Two annuals that reseed in our gardens are California Poppy (Eschscholzia californica) and Lacy Phacelia (Phacelia tanacetifolia).  Both of these plants are great for bees: California Poppy provides pollen and Lacy Phacelia provides nectar.

California Poppies

Lacy Phacelia

Lavender Hyssop is excellent for xeriscaping and provides nectar to wild bees and other pollinators.

Squash bees are native bees that can pollinate squash crops such as pumpkin.

A Xeriscape planting is one type of sustainable landscape, with the main goal being water conservation. By choosing drought tolerant plants that perform well in the local conditions, much less water is required to maintain them compared to grass lawns or traditional flower gardens. Another example is a pollinator friendly garden near agricultural areas. Pollinator conservation gardens help to conserve rare species and increase wild pollinator populations that can provide pollination services to nearby crops. The benefits include increased crop yields and more productive use of land.

Native plant species can be good choices for sustainable landscapes, but make sure they are matched to the project’s site conditions.  Evaluating site conditions is an important factor that is sometimes overlooked.  Using native seed, even if it is sourced locally, will not guarantee sucessful establishment at every project site.  Many urban environments have been substantially altered from the original conditions that existed prior to development by people.  For example, a shaded garden will not support native prairie plants that evolved in a sunny environment, even if the seed came from a natural area nearby.  Climate change may be an additional factor to consider in sustainable landscaping projects.

Commercial and residential landscapes can be environmentally friendly as well as attractive and functional. Diverse, permanent flower plantings and meadows in urban areas can help to reduce carbon emissions, increase biodiversity, provide ecosystem services, and even improve water management. The carbon footprint is a measure of the impact of human activity on the environment and is measured in units of carbon dioxide. The reduction of mowing and fertilizing in these plantings reduces carbon emissions. In addition, the direct sowing of seed produces fewer carbon emissions than nursery plants which generally require greenhouse production.

Ecosystem services are the resources and processes that are supplied by natural ecosystems which benefit people. Human activities have impacted the environment to the point where some of these services have been compromised. Long-term ecosystem health is being recognized as an important goal in order to maintain these benefits from nature.

A long-horned bee pollinating a native Clarkia flower.

One type of ecosystem service is the pollination of flowers. By planting pollinator habitats, wild bees and other pollinator populations can be conserved and even increased. These pollinators can contribute to crop pollination as well as the pollination of many flowering plants in wild areas. Plant communities that are maintained by pollinators are an important resource for wildlife because they provide food, shelter and nesting sites. The loss of pollinators, which are known as keystone species, would disrupt wildland ecosystems and have serious, long-term implications to the environment. The production of food crops that rely on pollinators will also be affected by the reduction or loss of pollinators. For these reasons, sustainable landscapes should include flowers and habitat for pollinators whenever possible.

One of the more interesting and fun aspect about my job is the work I do in our trial gardens.  Throughout the fall and winter, I gather ideas for new trials and look for seed sources.  In the spring, the fun begins.  The major part of our trials covers these categories: quality control on existing seed lots, new species or varieties, mixture trials, seed production trials, and variety improvement trials.  Of course the trial gardens also serve as a display garden for our customers and visitors.  Please take a walk through our gardens by clicking on the link below:

http://www.youtube.com/watch?v=Vw63hfWIMGM

Due to declines in the numbers of honey bees and wild pollinators, pollinator conservation has become a high priority in the United States, as well as other countries.  These declines have been caused by disease, pests, stress and habitat destruction.  There are 3 important requirements to consider for pollinator conservation: food, habitat, and safety.  Bees and other pollinators need food sources throughout their active season to insure good nutrition, which helps them to fend off disease and pests.  They also need habitat or areas where they can build nests and/or lay eggs.  Finally pollinators need protection from disruptive or deadly landscaping and farming practices.  If you have all 3 of these areas covered, you will be well on your way to conserving, and even increasing, pollinator populations on your property.  Today, I will be focusing on habitat for pollinators. 

Natural or Semi-Natural Habitat

A natural woodland with Bergamot (Monarda fistulosa)

If you have natural habitat or wild areas on your property, you can simply set it aside for pollinators.  These should be left undisturbed if there are adequate floral and habitat resources available.  The majority of wild bee species are ground nesters, and a minority utilizes wood, stems or twigs to build their nests.  Bumble bees nest in cavities underground, under clumps of grass, or in holes inside trees or walls.  Butterflies need protected sites such as trees, shrubs, tall grass, or piles of leaves or sticks. 

An ideal area to set aside is wooded land, shrubland or grassland that has an abundance of nectar and pollen rich flowers as well as some open, bare or partially vegetated ground with well-drained soil.  If possible, leave old, dead trees and shrubs in place for wood nesting bees.  If you must cut down dead trees for safety reasons, leave some of the limbs lying on the ground.  If the area looks unkempt and slightly cluttered with natural debris, it’s probably the ideal place for pollinators.

Even if you don’t have natural habitat, there are numerous options that might be available to you.  Marginal farmland that is inadequate for crops is often perfect for pollinator habitat.  Other semi-natural, undisturbed sites include meadows, field edges, buffer areas, roadsides, hedgerows, drainage ditches, and out-of-play areas on golf courses.  Homeowners and commercial business owners can install a pollinator flower garden and add hand-made bee nesting sites or natural objects that pollinators can utilize for nesting and egg-laying.

Constructed Habitat and Artificial Bee Nests

A queen bumble bee searching for a nest site in bunch grasses.

If you don’t have natural or semi-natural areas for pollinator habitat, you can build your own.  Choose an area for the pollinator habitat that is away from places where people are active.  For a natural appearance, sow native bunch grasses and wildflowers together.  Bunch grasses provide better nesting sites for bumble bees.  For ground-nesting bees, keep some areas bare where the soil is well-draining, or create unvegetated or lightly vegetated berms or mounds of sandy or silty soil.  Poor soils are actually preferred over rich, fertile soils.  Sites for ground-nesting bees should be constructed in open, sunny locations.

These are nest sites of ground nesting bees.

Stem bundles are fun to make.

For stem and twig nesting bees, you can make stem bundles, which are actually more like an apartment complex for bees.  These make great projects for children.  Like birdhouses, stem bundles are fun to make, and it’s exciting to see bees nesting in them.  Twigs of elderberry, sumac, raspberry, and blackberry are excellent for bees that chew out the centers of the stems to create their nests.  Bamboo stems, which are naturally hollow between nodes, can also be used for stem bundles.

To make a stem bundle, cut the twigs or bamboo into 8–12 inch long sections and tie them together with baling wire.  With bamboo, cut the pieces so that there is a node at one end and the other end is open.  The bundles should be about 3–5 inches wide so that you can still work with them by hand.  Creat a hook on the end of the wire to hang, or leave 2 long wires on the bundle so that you can twist them around posts, stakes, trees, fences or other sturdy objects in or near the pollinator habaitat.  The stems should be hung horizontal to the ground, and the bundles should be secured tightly so that they don’t move around by the wind.

Baling wire works well to tie stem bundles.

Drill holes of varying sizes in an old stump for wood nesting bees.

For bees that nest in wood, you can simply drill holes in stumps, tree limbs, and blocks of untreated wood or lumber.  Use a variety of drill bit sizes, ranging from 1/8 to 3/8 inch.  For holes 1/4 inch or less, drill the holes 3–5 inches deep.  For larger holes, drill 5–6 inches deep.  Set these wood objects in or very near the pollinator habitat. 

Maintenance

Once an area has been designated a pollinator habitat, then several maintenance practices should be followed.  Avoid disturbing the ground by digging, tilling, plowing or other means.  Never spray any insecticides in the area.  These will hurt or kill pollinators as well as the destructive insect pests they were meant to target.  Keep on top of weeds or unwanted vegetation by removing them periodically.  Finally, sit back and watch the pollinator activity for many years to come.

For more information, check out the Xerces Society for Invertebrate Conservation at www.xerces.org