Thursday, December 2, 2010

Planting for Butterflies

“Butterfly planting” is all the rage at the moment - and what beautiful results it will produce, as these gardens mature.
When planting for butterflies there are two main points to consider:
Things to do:
1. Plant flowers that adult butterflies will come to.
This is very easy. They don’t care whether their flowers are native or introduced. All they care about is that they have nectar (which is what adult butterflies live on), and most flowers have plenty of that. Excellent “butterfly-attracting” gardens are often produced by people who had never a thought of butterflies when they planted - they just planted pretty flowers.
2. Grow plants that caterpillars can grow up on. Each kind of butterfly has only a few “host plant” species that its caterpillars can eat. Without caterpillars, there are no butterflies - and those “butterfly-attracting” gardens which only considered flowers for the adults go begging.
Our suburban gardens are increasingly butterfly-deficient despite offering a smorgasbord of flowers. The reason? Bushland containing butterfly host plants is constantly being cleared as our suburbs spread. Each year, butterflies have further to fly, and often give those nectar-rich suburban gardens a complete miss.
To make a good job of creating a butterfly garden, you need first to know whether the “butterfly plant” you are contemplating is a host plant or merely a flowering plant. Then you need to have some idea of just which butterflies are likely to make use of the host plants. It’s no good planting a host for a butterfly which doesn’t actually occur in your part of Australia.
Most butterfly host plants are native, and local native host plants are the best choice, as they clearly work for the local butterflies!


A Blue Triangle.
These pretty butterflies need plants from the Laurel family (Lauraceae) to breed on. A good local native laurel is the small, shady, dry rainforest tree, the Bollygum, Neolitsea Dealbata.







The best source of information on plants to grow in our part of the world is a booklet called “Butterfly Host Plants of south-east Queensland and northern New South Wales”, written by John T, Moss. It lists 327 plant species for 201 species of butterflies, and is available from the Butterfly and Other Invertebrates Club, PO Box 2113 RUNCORN, Q 4113. You can email the club from this link:
http://www.boic.org.au/01_cms/details.asp?ID=3


Butterflies obviously love the nectar from these newly opened Callistemon flowers!

However, the success of this plant, which must have been feeding least thirty butterflies on the day I took this photo, depends heavily on its situation in a garden which is near bushland.
(The butterflies are: Caper White, Blue Tiger, Crow, Native Wanderer.)

Things Not to Do

1. Don’t Plant Environmental Weeds

Planting for butterflies is a great environmental initiative. It’s a pity to smirch it by planting environment-damaging species.
“Environmental weeds” are defined as plants which, though not locally native, spread (like natives) without any help from humans in the form of digging, planting, or watering. These plants are likely to jump your garden fence and establish themselves in the wild, or on the properties of your less-than-grateful neighbours.
Extra plants added to the wild are not mere harmless new arrivals, however much they may seem to be adding variety and colour to the bush. Each one takes up space which should be being filled by a native plant, and the long-term result is always less, not more, plant variety. Not only are native plant numbers reduced by their presence, the various animals (including butterflies) which needed the native plants for survival are reduced too.
Gardens don’t have to be restricted to native plants, however. There are plenty of lovely, easy-to-grow introduced plants, particularly ones with showy flowers which attract adult butterflies, which have shown no weedy tendencies. You can rely on them not to escape to make pests of themselves.
Unfortunately, environmental weeds are also readily available, and it is up to gardeners themselves to be discriminating. Potential weeds feature heavily among the ones typically given by helpful people to innocent young gardeners as garden starters. “This one will spread and fill the space in no time” they say - or “once this one gets going it just self-seeds and looks after itself”.
Reputable nurseries are usually - but not always - reliable in this regard, but weekend markets are great sources of environmental weeds. They are so easily reproduced that it’s no trouble to pot up these nice little money-earners by the hundreds.
And a few are even sold as “butterfly attracting” plants!

If you see non-native plants like the Coreopsis (above and below) growing on the roadsides, your "weed alert!" alarm bells should start ringing!

2. Don’t bother with host plants for feral butterflies.
We have a few of these, and they are doing very well indeed, thank you very much, not needing any help in the way of deliberate plantings in “butterfly gardens”.
One of these is the Wanderer or
Monarch, (Danaus plexippus) introduced into Australia (from America) in about 1880. Growing host plants for this one is like planting a “wildlife garden” then boasting about how many rabbits and pigs you are attracting!



An added disadvantage is that its milkweed hosts are very infectious feral weeds that your neighbours may get quite grumpy about.


Balloon Cottonbush Gomphocarpus physocarpus.
Avoid this feral weed, its very similar cousin
G. fruticosus, and their equally weedy friend the red-headed cotton bush , Asclepias curavassica


Cabbage White Butterfly, our other feral butterfly.
Distinguish it from some similar native butterflies by the black spots on the forewings - two for females, one for males.

This is now Australia's most common urban butterfly.
Is your garden attracting something better?

1 comment:

Blue Bird IM said...

This is a great article. I was wondering what the name of the yellow flower shown in this article is. We do not have these at our place, but our neighbours have them growing near the roadside, and I have always wondered if they were a native or a pest, thanks for the great information. Judi.