Plant Notes

WHS Plant Notes for October, 2008 

Abutilon X (MALVACEAE)
Flowering Maple, Chinese Lanterns
Grown by Barbara Worl in Menlo Park: 

	Abutilon megapotamicum

Abutilons are native to warm regions around the world with the majority of species occurring in South America. Most in the nursery trade are hybrids of various sizes, habits, and flower colors and forms. They're evergreen shrubs with fuzzy, green leaves that are more or less maple like and are sometimes nicely variegated by the abutilon mosiac virus. They bloom almost constantly with dangling bells of 5 overlapped petals in white or in every imaginable shade of pink, red, yellow, orange, and salmon and sometimes with contrasting veins and calyces. The flowers are magnets for hummingbirds and bees. Abutilons are so fast growing and bloom so quickly from cuttings that they're grown as annuals in colder regions. Moderate water and some afternoon shade is about all they ask for, but they're not pushy about those. They are, however, favorite targets of scale and whitefly, and most look better if pruned during winter to correct legginess. Abutilons had never thrilled Barbara, but she did grow a white one and one that looks like an A. megapotamicum cultivar with bright yellow petals just peeking out of a red calyx. When their hybrid progeny began to pop up in varying shades of yellow and pink, some with contrasting calyces, she became a fan and even bought more.

		Barbara bought 'Orange Hot Lava'. It grows 3-4' tall with red veined, clear orange petals held by a burgundy calyx.
	Abutilon "Orange Hot Lava"

She sought out 'Victor Reiter' because it was named for Victor. It is a sturdy, upright, 8' shrub with large, widely flared, salmon flowers with yellow-green calyces. The buds are like small, yellowish pumpkins. While looking for 'Victor Reiter', she bought 'Halo', a very floriferous, compact, 4' shrub with huge, flaring, pale apricot petals with red veins. It is her favorite now. 

Aster spp. (ASTERACEAE)
Grown by Barbara Worl: 

Barbara brought a few of her fall-flowering asters. They are fine textured perennials that cover themselves with small daisy like flowers at a time of year when most gardens need some fluffing. A. ericoides 'Monte Casino' is native to most of the states east of the Rockies. It grows to 4' tall with small, narrow leaves and tiny, yellow-centered daisies. The flowers can be white, pink, hot pink, red, purple or the lavender-blue of Barbara's plant. This aster is a favorite of florists and will last 2 weeks as a cut flower. When Barbara Hopper had her nursery, she gave Barbara an A. laterifolius that she had named 'Rubies in the Smoke'. Its ray flowers are white, the center disc is raspberry-pink, and its leaves turn coppery purple in fall. A. laterifolius is also native to eastern and central US. It takes part shade, grows to about 3' tall, and has a long blooming season from mid-summer to frost. She also showed an aster of unknown species that came from North Carolina by way of Betsy Clebsch. It had larger leaves and flowers like A. laterifolius.

Haemanthus coccineus (AMARYLLIDACEAE)
Blood Lily
Grown by Bill Kurtz in Santa Clara: 

	Haemanthus coccineus

It was great to have Bill back with us; and, to be sure we could recognize him after such a long time, he brought one of his signature South African bulbs with him. H. coccineus is summer dormant. It blooms just ahead of the rainy season and before it leafs out. The blossom has 6 to 9 stiff, red, petal-like bracts that surround a group of 25 to 100 tiny, red flowers with exerted yellow stamens. After the flower withers and rains begin, the bulb produces 2 opposite,strap-shaped, prostrate leaves that can be very long. Bill has had them grow to 32". They last until the bulb goes dormant for the summer. The flowers have no pollinators here; but, in South Africa, the flower is followed by a cluster of pink berries. When the berries ripen, the stem collapses to the ground where the seeds germinate immediately so that the new little plants can develop during the rainy season. They also produce offsets, but slowly. They are hardy to 24° F and tolerant of any soil so they can be planted here in a full sun location that stays dry during the bulb's summer dormancy. 

Pittosporum tenuifolium 'Silver Nugget'
('Argentea Nana') (PITTOSPORACEAE)
Grown by Kerry Barrs in Woodside: 

Kerry first saw this little shrub 6 months ago at a nursery in Mendocino. He could never find it around here and had to go all the way back to Mendocino for it. It's a dwarf form grown by Monterey Bay Nursery that will eventually be a dense, 4' x 3' mound of teeny-weeny, silvery foliage on black stems. The foliage is so congested that the stem ends look like bubbles covering the shrub. It is said to respond well to pruning so its a good choice for hedging, topiary and containers. It has a moderate growth rate, is very cold hardy, and will take full sun to part shade. 

Verbena hastata (VERBENACEAE)
Blue Vervain, Swamp Verbena, Simpler's Joy
Grown by Barbara Worl: 

When the owner of The Warward Garden nursery spoke to us a few years ago, Barbara bought this plant from her. It's a short-lived perennial that's native to most of the US and Canada and is usually found growing in disturbed, wet areas. It has a unique flower style for a verbena. From June to October, it makes candelabra-like, terminal panicles of slender, 5" long, flower spikes. A whorl of violet or blue flowers opens at the bottom of the spike and works its way to the top. The plants are 3'-5' tall with 5" long x 1" wide, coarsely toothed leaves. Give it moist, rich soil in full sun or a little shade. This plant has had many medicinal uses. Many bee and butterfly species nectar on it and birds love the seeds. And, as Barbara has noticed, it does make lots of seeds.

Xanthoceras sorbifolium (SAPINDACEAE)
Yellowhorn, Chinese Flowering Chestnut
Grown by Betsy Clebsch in La Honda: 

	Xanthoceras sorbifolium

This is a native of northern China that's not often found in the nursery trade in spite of being introduced over a hundred years ago. It's a stiffly upright, deciduous tree or large shrub. Betsy brought a branch with one of its interesting seed pods. It had lacy, compound leaves of 9-17 narrow leaflets with serrated margins. The seed pod was a hard, green, tennis ball sized, oval pod whose 3 valves had begun to separate showing its thick, pale beige walls and the dozen or so dark brown seeds inside resembling small chestnuts. As Katie Wong pointed out, these are edible and taste like macadamia nuts when roasted. Hopefully, Betsy will bring a flowering sample next spring. It blooms in dense,10", upright racemes. The flowers are nicely fragrant, 1" wide, and look like slightly ruffled stars. The petals are white with a basal blotch that starts out yellow and ages to pink and then rosy red. All the color stages are present at the same time. It blooms on the previous year's growth and needs summer heat to fully ripen the wood and stimulate production of flower buds that are destined to bloom the following spring. It can be slow to establish; but, at maturity, it will be 18-22' tall x 10-15' wide. It prefers a warm, sunny location in any soil with reasonable drainage, including slightly alkaline clay, and tolerates some dryness.

Jackie N. Doda

References: Am. Hort. Soc. A-Z Encyclopedia, Botanica, Flora, Sunset Western Garden Book, and various websites.