[Ed note: Pictures of their favorite flowers and the associated butterflies are posted in the order listed by Penny Pawl.)
This has been a beautiful, bountiful year for butterflies in my garden. I have been hand-raising butterflies for many years now. It's my effort towards giving them a better chance at life.
Butterflies start in March when the flowers and vines begin to put out flowers and leaves. The Dutchman's pipevine (Aristolochia macrophylla ) puts out its little pipes in March. These blooms are pollinated by gnats. The leaves start to grow about the same time, and the Pipevine Swallowtailbutterflies are programmed to leave their pupae at this time. Most of them have been waiting almost a year to complete metamorphosis and are happy to be flying in the sun, gathering nectar from flowers and laying eggs.
When I see a female laying eggs, I search through the vine and usually find eight to ten little golden eggs in a cluster. Before a predator can get to them, I take the eggs in the house and put them in a small container. The container keeps them and the leaves from drying up. In less than a week, the tiny caterpillars are born. At that point, I know that I am committed for five weeks before they will make a pupa.
Once I commit to raising them, I clean their containers daily and make sure they have plenty of pipeline leaves, their preferred food. Occasionally I run out of leaves from my vine, but I know where another vine is and I will 'borrow' some of its leaves.
Monarch butterflies make their first flight through Napa Valley in April and May, heading north. To be ready for them, I grow a number of types of milkweed (Asclepias) that bloom at different times in spring and summer. The native milkweed (Asclepias speciosa) is usually growing when the Monarchs pass through. They may lay eggs if the plant has tender young leaves.
This past spring I gathered about 20 Monarch eggs. They are small, white and found on the underside of milkweed leaves. When I gather the eggs, I take a piece of leaf with me so when the eggs hatch they have some food. Right now the butterflies are ignoring Asclepias speciosa as the leaves are old. Instead they are laying their eggs on narrow-leaf milkweed (Asclepias fascicularis). I have lost count of the number of Monarchs I have raised in my house this year, but it must be around 50.
I was gone for a couple of weeks in June when another group of Monarchs came through the garden. Every milkweed variety that I grow had been munched. I found caterpillars of various sizes and took them inside to complete their growth. Monarchs take less than three weeks to mature and become a pupa. They will emerge from the pupa in another two weeks. Since they are hatching in my yard and I have plenty of flowers, they stay a while and lay more eggs.
Anise Swallowtail Butterflies feed on fennel (Foeniculum vulgare) and members of the parsley and carrot family. My fennel had struggled for years as gophers love it, too. I finally put the plant in a large pot to protect the roots and sunk the pot in the ground. The roots grow out the holes in the pot and the main plant is saved. This seems to work, and I have found tiny caterpillars on the fennel. So far this year, I have more than 20 that are either in pupae or eating fennel like there is no tomorrow.
All three of these members of the Swallowtail family taste bad to birds. However, that does not stop spiders, wasps and native bugs from dining on them. Lizards also like them. A few years ago, small parasitic flies laid eggs in one group of Anise Swallowtails I was raising. This killed the caterpillars when the eggs hatched.
These butterflies live only six to eight weeks. During that time they will lay 500 to 600 eggs. Not all the eggs are fertile; some are defective and the newborns die before they mature. But by hand-raising them, I am giving more butterflies a chance to have their flying days. In nature, only a small percentage make the transition.
When I started raising the Pipevine Swallowtail, I saw only a few, but now many visit my vine all summer long. Last year, in late September, two large Pipevine caterpillars were still feeding on the vine.
You don't have to hand-raise butterflies as I do, but you can help them survive by planting nectar plants. Grow native Pipevine, native milkweeds and other plants that butterflies need to lay eggs and feed. Never use pesticides; butterflies are not immune.
Gardening for Butterflies is an excellent resource. You'll also find a lot of good information on the life cycle of butterflies online.
Tree Walk: Join U. C. Master Gardeners of Napa County for a free guided tree walk through Fuller Park in Napa on Monday, September 12, from 10 a.m. to 11:30 a.m. Registration is recommended as space is limited. Meet at Fuller Park, corner of Jefferson and Oak Streets. Online registration or call 707-253-4221. Trees to Know in Napa Valley will be available for $15. Cash or check payable to UC Regents. Sorry, we are unable to process credit cards.
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.