Winter bee blooms

Sunday, 24 July 2016

Grevillea commutata, Kings Park and Botanic Garden, Perth WA

I have written about bees previously in a blog, and discussed how these indispensible creatures currently face many threats, including diseases and mites; loss of habitat and plants for foraging, because of urbanisation and modern agricultural practices; and poisoning from certain pesticides used in agriculture and gardens, particularly those from the neonicotinoid class (which includes Confidor). Bees are the most important insect pollinators of flowers: essential for the production of fruit, certain vegetables and agricultural crops, as well as flower and vegetable seeds. One thing that gardeners can do to help bees is to grow plants that are abundant in nectar and pollen in their gardens.

In winter, bees are less active in our gardens. Once the temperature drops below about 15 C, they head to their hives - and who can blame them! They apparently gather in a central area and form a cluster around the queen bee to keep her warm. By fluttering their wings and 'shivering', the bees keep the hive at the right temperature. The bees rotate their positions from the outside to the inside so no individual bee gets too cold. They rely on stored honey for energy. However, on mild winter days in Sydney (such as the three we experienced last week!), bees will leave the hive to forage. In late winter, the colonies start to build up their numbers again, and need fresh fresh sources of food.

Banksia species can be a good source of food for bees in winter

I like the idea of growing some winter-flowering bee plants to encourage them to come into my garden in the cooler months. Obviously, the flower palette is much diminished at this time of year, but there are plants blooming that do entice the bees with nectar and pollen. Much of our native flora provides excellent floral resources for bees, and examples in bloom now include Grevillea, Acacia and Banksia species. There are compact varieties of some native plants available nowadays that are suited for home gardens.

Lavandula dentata in the garden of Sue Daikin in Sydney

Numerous introduced plants are also very attractive to bees. Flower shape (providing ease of access to pollen and nectar, with single-form blooms being the most sought after) and colour (they are said to be particularly drawn to the colours blue, purple and yellow) seem to be important determinants of the appeal, and certain plant families seem to have a special attraction. One of the most important of these is the mint family (Lamiaceae), which contains many herbs as well as garden flowers that bees adore. Most of these bloom in the warmer months, but French lavender (Lavandula dentata, ht 1 m) is in full flower through winter in Sydney, and is actually one of the best sorts of lavenders to grow in our climate. It does best in a sunny position with dryish, well-drained soil. Every few years, it needs to be replaced with a fresh specimen. Salvia is another genus in the mint family, and there are some winter-flowering species and cultivars that can attract bees, such as 'Amistad', Salvia fallax (now known correctly as Salvia roscida), Salvia rubiginosa and Salvia elegans Purple Form. I don't cut back my autumn-flowering salvias such as 'Meigan's Magic' until August, as bees seem to still forage on the ageing blooms.

Tagetes lemmonii blooms through winter and attracts bees

Bees love daisy flowers, but there aren't so many of these around in winter. One that does bloom now is the so-called mountain marigold (Tagetes lemmonii), a shrubby perennial with brilliant golden flowers, held amidst passionfruit-smelling foliage! An unlikely member of the daisy family, perennial Ageratum houstonianum, flowers all year round in my garden and attracts bees with its fluffy, blue, nectar-rich blooms.

Lobularia maritima flowers all year

Winter-flowering annuals are often bee-magnets: the lacy, fragrant clusters of alyssum (Lobularia maritima (pictured at left), colourful Shirley poppies, dainty Nemesia coerulea and cheerful single-flowered pot marigolds (Calendula officinalis) all buzz with bees on a sunny winter's day. I've noticed that other favourite bee plants in my winter garden are those vestiges from my English cottage garden years: the ones that actually do OK in Sydney's climate, including perennials such as hellebores, Bergenia, winter wallflower (Erysimum mutabile) and sweet violets (Viola odorata). Ever-blooming Euphorbia 'Diamond Frost' is another favourite.

Chaenomeles speciosa is a good bee plant in the cooler months

There are also some classic evergreen winter-blooming shrubs that attract bees: Mahonia and Sarcococca species, and Viburnum tinus, with its pinkish-white posies. I've only recently developed an appreciation for these as stalwarts in the garden, providing permanent structure and an elegance that semi-tropical shrubs - with their brittleness and need for frequent pruning - seem to lack. Winter-flowering deciduous blossom trees are also attractive to bees, such as the flowering quince (Chaenomeles speciosa) with pink, white or red flowers; and the Taiwan cherry (Prunus campanulata), with its carmine, bell-shaped blooms. The latter is one of the few cherry trees that performs quite well in the Sydney climate. Established lemon and lime trees often bloom through winter, drawing bees to this source of nectar.

Bee plants are best grown in full sun, as they often ignore those grown in shade. They also dislike strong wind, so providing shelter from wind is a factor. Bees also need water: wet sand, a shallow-edged pool or a birdbath with stones in it can all be provide a suitable source. Avoiding the use of pesticides toxic to bees is also very important. I really implore people not to use Confidor in their gardens, either in its spray or 'tablet' form. This chemical is responsible for a decline in bee numbers worldwide.