Sunday, February 04, 2007

Bulbs

What’s blooming outside: Nothing.

What’s blooming inside: Aptenia, zonal geranium.

What’s green and visible in the area: Needle grass and other unidentified grasses: yucca, yew, juniper, arborvitae, piñon and other pines.

What’s green in my yard: Rose stems, rockrose, Mount Atlas daisy, horseweed.

What’s gray: Snow-in-summer, buddleia, pinks, Greek yarrow, golden hairy aster, four-winged salt bush.

What’s red: Cholla, coral bells, pinks.

Animal sightings: Wednesday, scared up a large-eared rabbit who bolted for the empty lot across road.

Weather: Snowed Tuesday night. Warm temperatures Wednesday softened the ground and turned the snow to slush which has been freezing every night since in places where it has not evaporated or melted.

Weekly update: Theory and reality clash here.

Bulbs ought to grow. After they bloom in April and May, the leaves carry nutrients down into the bulb, where the plant creates embryos of next years flowers and leaves. During the summer heat and drought, after the leaves have died away, cell division slows, earlier for Daffodils than for Tulips.

In the fall, after the monsoons have brought new water, bulbs put out new roots. The cold slows elongation of flower stalks, redistributes water within bulbs, accumulates nitrogen in roots and converts starch to sugar which is transferred to developing shoots.

In 1997 I planted tulips and daffodils on the east side of the house, and absolutely nothing came up.

It’s pretty hard to fail the first year with healthy bulbs. After all, they’ve gone through the regeneration process in the hands of skilled nurserymen. I blamed in on the gopher who may have eaten the tulips and removed the dirt under the poisonous daffodils, and decided anything that attracted that mammal wasn’t worth the risk.

Years passed. I noticed red and yellow tulips never seemed to survive for more than a year or so in anyone’s yard. I also noticed grape hyacinths I planted in 1997 on the west side of the house were thriving.

I thought perhaps bulb catalogs were misleading when they said bulbs only needed cold for 13 to 14 weeks. When they’re put in a refrigerator at 35 to 48 degrees, temperature and humidity conditions are uniform. Snow does more than chill: it puts moisture on frozen ground ready to sink in, protects that water from drying winds, and insulates the ground against wide temperature changes.

On the east side of my house, the snow melts quickly. This year it has been bare and recovered at least five times. The west lies in the shadow of the house, and has been snow covered since late November. There’s 2 to 6 inches there now.

The point of cooling bulbs is to recreate their natural conditions. Narcissus Pseudonarcissus, the parent of domestic daffodils, is from the Cordillera Cantábrica of northern Spain and Portugal. When it naturalizes in England, Caldwell and Wallace observed it prefers southern or western exposures, often in damp, poorly drained soils. Other have found it likes heavy clay.

Tulipa Genisarias, the progenitor of hybrid tulips, had been cultivated by Moslems for centuries when they were discovered by Europeans. M. H. Hoog found the primary gene center for the genera lay in the Pamir Alai and Tien Shan mountains. The geophytes diffused from there to the Caucasus where a secondary gene center developed. Modern tulips are from the eastern Crimea, just west of those mountains.

Española lies at about 6,000' at 36 07 N latitude. The Iberian mountains are at 43 00 N, while the Caucasus are at 42 00 N and the Crimean at 45 00 N. Our average rainfall is 10" a year, while it's 21" in Leon south of the Cantabrians, and 14" in Feyodosia at the east end of the Crimea. We may get more sun and less precipitation, but our hot dry summer, cool wet winter seasonal patterns are similar.

In 2003, I decided to try again, this time on the west side of the garage that so far has never seen a gopher. The snow disappears a little sooner there than by the house, but the water that drips off the metal roof has dug a furrow that fills with ice in winter.

I planted four varieties of tulips among exiting plants between the garage and the drip line, then put a mixed bag of daffodils between the furrow and grass, just beyond the existing plants.

The first year, most of the tulips and many of the daffodils bloomed. The stems were a little shorter than advertised, but otherwise there they were. They’ve now bloomed three years, with increasingly shorter stems, perhaps because the past few winters have seen little snow. The number of tulips has remained constant, the number of daffodils has declined leaving only the best adapted varieties.

They’ve passed the first test, and probably can survive for years, as they are. Genuine colonization won’t occur until the bulbs clone themselves. In the best conditions, daughter bulblets take three years to flower. Here in the hostile, dry rio arriba those fertile years may be spaced by seasons of dormancy.

For now, the snow promises they should break ground in March and bloom another year.

Notes:
Caldwell, John and T. J. Wallace, "Narcissus psudonarcissus L.," The Journal of Ecology 43:331-341:1955.

Hoog, M. H, "On the Origin of Tulipa," Lillies and Other Liliaceae, Royal Horticultural Society, 1973:47-64, summarized by many, including Richard Wilford and the Missouri Botanical Garden.

Kilsdonk, Maria Gerarda van. Assessment of the Internal Quality of Stored flower Bulbs using Magnetic Resonance Imaging, 2002, "General Introduction" available on-line.

Picture: West side of garage, 31 January 2007. Snow covers daffodil bulbs. Tulips are between the ice and stucco wall. Vegetation includes needle grass, phlox. purple coneflower, and Silver King artemisia.

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