Geraniums paralyze Japanese beetles

Another rainy day in the 50s.  I’ve taken the last languishing 'house' plants outside and lined them up on the mudroom steps to soak in the rain.  The only summer container plants that really survive my brutal care are the common geraniums, Pelargonium zonale.  

I wouldn’t say they thrive on winter neglect and the bone dry potting soil that surounds their roots on the backstairs windowsills, but they live to see another summer.  They’re also the only plants that thrive in the summer under my (non)watering scheme.  I’ve been tempted to ONLY plant geraniums in previous years -- partly inspired by the incredible window boxes and containers of geraniums we saw in the Alsace Lorraine a couple of years ago.  Now there is an even better reason to fill the garden with common geraniums.

Scientists have known since the 1920s that geranium flowers appear to both attract Japanese beetles and paralyze them -- the beetles become so intoxicated by the petals they pass out for 12 to 18 hours which in the wild can be a lethal binge.

Recently UK entomologists Daniel Potter and David Held have studied this phenomenon further to discover what causes this reaction.  Japanese beetles are the scourge of home gardeners and retailers -- eating over 300 types of plants and 79 plant families.  Almost all of the states east of the Mississippi River except Florida suffer incredible financial damage from greedy beetles, and the U.S. Department of Agriculture is keen to prevent the beetles spreading to the western US where they could devastate California vineyards and crops.   An effective and earth-friendly way of exterminating Japanese beetles would be a goldmine and the geranium’s knockout punch seems to have great potential.

 "We found that when Japanese beetles fed upon the petals of geranium, generally in less than an hour the bugs enter a kind of narcotic state," says Potter. "They curl up on their back and pull their legs close to their underside. They'll twitch if you disturb them, but they're clearly in dreamland."

Funded by the USDA, Potter and Held have found that the bugs seem unable to resist geranium temptation -- when beetles were given a choice between nutritious linden plants and mind-blowing geraniums they overwhelmingly went for the geraniums and ended up on their backs.  Nor did they learn from their mistake, every time they recovered from their geranium-trip they ignored the healthy choices and chomped down on almost 10 times the previous amount of geranium petals before becoming intoxicated again.  Interestingly, geraniums grown in full sunlight packed more of a gastronomic punch for the beetles.

Potter's team also reared pairs of beetles in boxes with soil so that they could lay their eggs the beetles. One group received the healthy linden leaves, one group received the geranium petals, and one group received an equal amount of both.

"As one would expect, the group that got the linden leaves lived long and happy lives and laid a large number of eggs," says Potter. "Both groups with access to geranium spent the better part of this two-week experiment on their backs in a narcotic state, had a much higher mortality rate, and laid very few eggs."

With the help of plant chemists at Cornell, UK researchers are testing various geranium chemicals on the beetle-favorite Virginia creeper, and they've been able to duplicate the geranium's narcotic effects. Potter says that by this coming summer they'll have identified the exact extract which should be invaluable in creating effective Japanese controls.

"One of my goals is to understand the insect better," says Potter. "I think if you understand the biology of a pest insect, it opens up new avenues for management that are environmentally more responsible."

The Japanese beetle's behavior makes it an interesting insect to study, Potter says.

"I really like the Japanese beetle. It's my bread and butter insect. It's a great bug, sort of The Terminator of the insect world."

Maybe this summer I actually will create an Alsace inspired geranium display and sit back with a glass of  Riesling to watch the beetle show.

Lindera benzoin

A native shrub that has naturalized throughout our woods.  We are constantly digging up spicebushes from the woods edge as they threaten to take over the garden -- initially we tried to move them but they are notoriously difficult to transplant because of their coarsely fibrous root system and are very slow to reestablish.

This time of year they are in their glory, a wonderful chartreuse haze that brightens the woodland understory.

The Facts

Family: Lauraceae
Genus: Lindera Species: benzoin Common Name: Spicebush
Area of Origin: Maine to Ontario and Kansas, sought to Florida and Texas
Characteristics:  Alternate, simple, oblong-obovate leaves, 3" - 5" wide, light green above, pale underneath.  The flowers are dioecious, yellow and tiny, appearing late March to early April before the leaves.  Not overwhelming to look at but fabulous en masse.  The fruit is an oval drupe, about 1/2" long and scarlet but is seldom seen since it is showy only after the leaves have fallen.    The shrub grows 6' - 12' tall with a similar spread, although the national champion in the Jefferson National Forest in VA is 20' x 20'.  It's a rounded shrub in outline, rather loose and open in the wilderness of our woods, supposedly full and dense in full sun.  The leaves turn a wonderful golden yellow in the fall.
Hardiness: USDA Zones 4 to 9 

Cultivation needs: Best in moist, well-drained soils, full sun or shade, can cope with dry soil.
Typical Pests, Diseases, associated problems: None to speak of.
Propagation Method: Seed needs to be stratified, cuttings will root but percentages not high.

Dominique Browning was the editor of House and Garden for 12 years.  It was one of my favorite magazines and I was sad when it folded suddenly, seemingly without cause.  It happened just after I left the editorial world and slid into garden design.  I used to look forward to reading Dominique's editorial letters and following her life vicariously through them.

House & Garden was a magazine that celebrated the good life, I haven't found a similar one in this country and now subscribe to the UK version.  Dominique Browning now writes a column for the Environmental Defense Fund Web site and has a new blog, SlowLoveLife.com.  Below is an extract, via the New York Times, from “Slow Love: How I Lost My Job, Put on My Pajamas and Found Happiness,” to be published next month by Atlas & Company.  It's a wonderful description of spring unfolding.

"I took to wandering in my garden at all hours. As if to give me one last chance to change my mind about leaving, spring unfolded in splendor. The daffodils multiplied generously and spilled across the front in a riot of gold. Bunches of hellebores appeared in March and nodded their prim white, mauve and purple caps for more than two months; when I bent down to turn up a small head and peer into a quiet, trusting face, I winced at the thought of leaving them vulnerable to whatever depredations a new owner might visit upon them. I apologized in anticipation. I strolled the paths, examining the thick, furry spools of the unwinding ferns; the gnarled purple fingers of the peonies clawing out from the damp, fragrant earth; the green stubs of the Solomon’s seal; the sharp tips of the hosta encircled by improbably large patches of bare ground that would soon be hidden by gigantic leaves, bearing aloft the fragrant white wands that seduce the moths at dusk......

......One adventure is over; it is time for another. I have a different kind of work to do now. I am growing into a new season. At the water’s edge, watching the tiny, teeming life of that mysterious place between high and low tides, the intertidal zone, I begin to accept the relentless flux that is the condition of these days. I am not old and not young; not bethrothed and not alone; not broken and yet not quite whole; thinking back, looking forward. But present. These are my intertidal years.

In those sleepless nights, when I am at the keyboard, I connect with something I may have once encountered as a teenager and then lost in the frantic skim through adulthood — the desire to nourish my soul. I do not have the temerity to think I have found God; I think instead that I have stumbled into a conversation that I pray will last the rest of my life."

Camellia japonica

What a difference a few days of spring sunshine makes.  On the 21st the camellia buds were furled tight.

This morning when I made my daily rounds they were beginning to bloom.  Of course the shrubs in the supposedly ideal position in the well drained sheltered beds in front of the house are still languishing while those planted haphazardly at the edge of the woods in the back are thriving.

The Facts

Family: Theaceae
Genus: Camellia Species: japonica Common Name: Japanese Camellia
Area of Origin: Japan
Characteristics:  Alternate, simple, evergreen, ovate leaves, 2" - 4" long with a firm leathery almost plastic texture.  The flowers are perfect, mainly non-fragrant, solitary and come in white, pink, rose, red and every conceivable combination included variegated.  Their biggest enemy is the cold which turns the flowers to brown mush -- they're exquisitely beautiful when not adulterated by the weather.  The bushes themselves form a dense pyramid of lustrous dark green foliage, some cultivars are more graceful in form than others but on the whole they form a stiff, formal splodge of green.
Hardiness: USDA Zones 7 to 9 (though we're 6, hence the very sheltered position).
Cultivation needs: They transplant easily from containers but I would caution against planting in the fall.  The first year we moved here I excitedly planted half a dozen and lost all of them that first winter. They seem to do much better when planted in the spring.  They prefer moist, acid, well-drained soils with high organic content.  It's advisable to mulch as the roots are shallow, they should be sited in partial shade as too much sun or shade affects the flowering -- which is really the only reason you'd plant them.  Prune after flowering.  It's important to choose cultivars carefully and pick one that is hardy in your area.
Typical Pests, Diseases, associated problems: Spot disease on leaves, black mold on leaves and stem, leaf gall, flower blight, leaf cankers, tea scale, mites, cut-worm, mealy bugs, weavils, thrips, numerous other insects, chlorosis, sunburn, oedema, physiological disorders including bud drop .... I'm glad I didn't read the list before planting.
Propagation Method: Seed requires no pretreatment if taken from the capsules and planted immediately.  If allowed to dry out they need to be covered in hot water and allowed to imbibe for 24 hours before being planted in seed flats.  Cuttings are best collected from May to September and in the fall.  Also good grafted and air-layered.

Vining peas

The last of the peas are planted.  I reused last year's tomato stakes and nailed 1" x 3" lathes to the top to secure the trellis.  My fingers froze again as dug the trenches.

Planting peas

The first of the peas went in today.

2000 peas to be exact, two 40' rows of shelling peas "Strike" (one of the earliest and just 24" high) and two rows of "Caselode" which is one of the sweetest shelling peas and slow to turn to starch when the weather warms so although producing later it has a long harvesting time. Better late than never, but definitely late.   Peas are normally planted around St Patrick's day (March 17th) or as soon as the ground is workable and has had a chance to dry out a bit after winter.   It will be a few weeks before they look like the crop below

I dusted them with a bacterial inoculant to help increase yields and then zigzagged the seeds 1/2" apart in a 3" shallow trench.  It's always good to follow the old tale of one for the mouse, one for the crow, one to rot and one to grow.  To safeguard against mice it's a good idea to cover them wire netting, although I must confess I never do.  

I love shelled peas, harvested and eaten straight from the vine, there is nothing like them and buying the dried out starchy pretenders available in stores comes nowhere near the real thing.   Peas are cool-season performers and you have to plant a lot to ensure a good size pea harvest once they’re shelled -- hence the thousands planted today.  Not that I plan to actually eat all that I plant, they freeze well and this year I tend to extend the growing season by harvesting and eating some of the young pea shoots and tendrils.

All parts of the pea plant are edible. As the pea leaves and stems mature, they tend to get tough and stringy. But when they are young, the pea shoots with their curling, clinging tendrils are tender and delicious.  The great thing is that although they look exotic and sophisticated on the table even gardeners who can’t grow peas to maturity can grow pea shoots and tendrils.

There’s no trick to growing pea shoots and tendrils.  Just seed extra so you have some to harvest early. Since the plants you sow for shoots and tendrils won’t need as long a growing period, you can reseed up to about 1 month before the warm weather sets in.

Once the pea plants are about 6" - 8" tall, you can snip off the top growth including one set of leaves. This will be your first, small harvest, but cutting off the growing tip will encourage the plants to branch out and continue growing.

After that, you can continue harvesting the top 2" - 6" of the pea plants every 3 - 4 weeks. You can harvest shoots, leaves and tendrils as well as any flowers or buds that may have formed.  Eventually the plants will cry uncle and start to turn bitter, best to stop harvesting at this point.  Last year the weather was so cool I actually got pea pods forming on these plants, most years the pea season is well over before then.  No worries, you can replant from seed in mid-August for a fall crop.

Daphne odora

I first encountered Daphne odora at an open garden in Devon 10 years ago this month.  The fragrance wafted across the garden, I traced it to this compact gloriously flowering shrub that I HAD to have. 

I bought a plant on the spot from the garden's small shop and carried it through Devon and back to Buckden where I kept it in a pot and then gave it to my mother-in-law when we moved. It was one of the first shrubs I bought when we moved here.  I have it in the shrub border by the kitchen window where I can breathe it's fragrance deeply when I venture out the mudroom door and can open the kitchen window and fill the room with scent.

The Facts

Family: Thymelaeaceae
Genus: Daphne Species: odora Common Name: Winter or Fragrant Daphne
Area of Origin: China
Characteristics:  A densely branched, mounded evergreen shrub that reaches 4' (6') in height and width.  Alternate, simple, evergreen, leathery, elliptic-oblong leaves.  The fragrant, rosy pale pink/white flowers are borne in 1" diameter, terminal heads with up to 10 florets during February - March.  They last a long time and the fragrance is wonderful.  Fruits are supposedly red but I've never seen one.  It performs well in shade and is not meant to be as finicky about soil as other Daphne species.  Dirr says "What a wonderful plant!  Temperamental, trying, but worth all the attention."
Hardiness: USDA Zones 7 to 9 (though we're 6, hence the very sheltered position).
Cultivation needs: Temperamental, reportedly short lived, prefers part shade. They dislike disturbance and once planted should be left there.  Sometimes they die for no apparent reason, very fastidious about culture, overly wet soil appears to doom them.  Still a plant of the first order that is absolutely stunning in flower
Typical Pests, Diseases, associated problems: leaf spots, crown rot, twig blight, canker, viruses, aphids, mealybug and scale.
Propagation Method: Dirr used to think propogation was as "easy as cutting warm butter" but now claims to have varied success.  Timing seems to be important when gathering cuttings, covered frame and shade cloth etc.  To the nursery I go.