California pipevine

Aristolochia californica, California pipevine or California Dutchman's-pipe, native vine flowering with chrysalis of Pipevine Swallowtail butterfly

Aristolochia californica, California pipevine,  with chrysalis of pipevine swallowtail butterfly

California pipevine (Aristolochia californica) is one of the first plants to flower in my northern California garden, sending forth dozens, no hundreds, of tiny blossoms on leafless stems in mid-winter, after the manzanitas but before flashier plants such as native irises grab center stage.  Their appearance, noticed only up close at first, signals the approaching end of winter and fuels my anticipation of full-on gardening weather.

The flowers are, to say the least, unusual.  They grow more like fruits than flowers, maturing, right before your eyes, from a millimeter or two to an inch and a half long on the vine.  Most plants hide their flowers in one way or another before they spring into view, full size, at maturity.  On plants of California pipevine, you can see the tiniest immature flowers alongside partially mature and mature flowers at the same time.  I go out daily to check on the progress of tiny flowers I saw the day before.

Aristolochia californica - Dutchman's Pipe, flowering California native plant

Aristolochia californica flower

Reputed to prefer lots of moisture, even riparian sites, California pipevine seems to do quite well with little or no summer water in shade to part shade or at least afternoon shade, even on the inland side of central California’s coastal hills.  While the upper leaves seem to like some sun, the roots must be cool, especially in hot summer weather.  I have one planted in an oversized clay pot that receives morning sun but is fully shaded on summer afternoons by a second-story deck.  I attached the vine to a deck post and strung it along the joists, mostly because I wanted to see the details of the individual flowers and the bright green heart-shaped leaves.  In nature it is often a tangle of stems with a mass of old leaves along with the new, as some spent leaves tend to stay on the plant well into the following year.

California pipevine is the only host plant of the native pipevine swallowtail, which is why I planted it in the first place.  I have yet to see a single caterpillar on my plants, but hope, even hope in vain, is what keeps gardeners going.  The leaves are said to produce a toxic chemical that, when ingested by caterpillars, makes them and the butterflies they become unattractive to predators.  I cannot attest to any of this as I have not seen a pipevine swallowtail in my garden.

Aristolochia californica, California pipevine or California Dutchman's-pipe, native vine used as sprawling vine on hill by steps in Schieffelin native plant garden

Aristolochia californica, California pipevine, used as sprawling groundcover

You will hear that California pipevine is slow to start, even hard to grow.  That has not been my experience.  The first year I planted my vine in the pot underneath the deck it was ripped out, likely by a raccoon.  I stuffed it rather hastily back in the pot, unwilling to just let it go, and in weeks it was showing signs of new life.  The first year it grew perhaps six feet tall, no flowers.  The second year it had many flowers and had extended its reach perhaps twice that high.  By the third year it was covered in flowers and had reached more than twelve feet.  This winter, six years in, it is easily fifteen feet in full extent and the flowers are coming out an inch or two apart.

This is a vigorous, robust, vital native California plant with great habitat value, well worth a place in any summer-dry garden.  It is native to central and northern California in foothill woodlands, chaparral, and mixed evergreen forests, usually but not always on sites that provide at least some moisture year-round.


California wild grape

Vitis californica 'Roger's Red' in fall color

Vitis californica ‘Roger’s Red’ in fall color

California grape (Vitis californica) is a large, fast-growing, deciduous vine that provides quick summertime privacy and shade as well as brilliant yellow, orange, or red fall color.  In summer or fall, the lush foliage is thrilling when backlit by afternoon sun.

Native to riparian areas of California and Oregon, this headstrong vine grows thirty feet tall and wide with its preferred regimen of shaded roots, tops in full sun, and moderate summer water. Vines climb by tightly twining tendrils that stand firm against the most determined pulling and will advance high into trees and smother nearby shrubs if unrestrained.

Happily, this rampant tendency can be harnessed to benefit the gardener.  One or two plants can be counted on to cover the largest trellis, fence, arbor, or shadehouse in three to five growing seasons.  Growth can be restrained with restricted summer watering and vigilant pruning.

Summer watering is a balancing act, as monthly deep watering – twice monthly or weekly inland – usually is required to avoid early dropping of leaves, which means loss of the glorious autumn show.  Mulch the base of the plant to conserve moisture and water only as needed to offset early morning wilting.  Afternoon wilting of the large leaves is expected in the hottest weeks of summer.

California grape provides cover and food for birds and other wildlife.  Deer may browse the leaves and new stems.  Fruits are edible and tasty but have large seeds and little pulp.  Fruits hang on the vine until they are eaten by birds or turn into raisins, and leaves drop cleanly in fall.

There are several named varieties of California grape.  Surely the most vigorous and striking is ‘Roger’s Red’, with apple green leaves that turn bright scarlet in fall.