Fall Roses

What’s blooming in the area behind the walls and fences: Hybrid tea roses, silver lace vine, Japanese honeysuckle, sweet pea, alfalfa, Sensation cosmos, French marigolds, zinnia; trees of heaven turning yellow with cottonwoods and catalpas.

Outside the fences: Apache plume, yellow evening primrose, datura, white sweet clover, áñil del muerto, spiny lettuce, purple, heath and golden hairy asters.

In my yard looking north: Nasturtium, chocolate flower, blanket flower, Mexican hat, black-eyed Susan, yellow cosmos, chrysanthemum, Crackerjack marigold.

Looking east: Hollyhock, winecup, Jupiter’s beard, pink evening primrose.

Looking south: Blaze, floribunda and miniature roses; daylily leaves bright yellow.

Looking west: Russian sage, catmint, lady bells, calamintha, Mönch aster; yellow peach leaves beginning to accumulate.

Bedding plants: Moss rose, snapdragon, nicotiana, sweet alyssum.

Inside: Aptenia, asparagus fern, pomegranate.

Animal sightings: Rabbit, black harvester and small red ants.

Weather: Storms in area most of week; soaking rain early Thursday morning; 11:00 hours of daylight today.

Weekly update: When I was a child, roses were meant to be picked. One was told to prune to produce large, magnificent blooms like those my mother floated in clear glass globes.

Someone in the village has such a cutting garden, a bare rectangle with six roses lined in two columns. Each gets about 3' high and 2' wide and carries large, florescent flowers at the tops of its thorny stems.

At a former bank near the old post office someone else planted hybrid teas in gravel mulch that rarely seems to get pruned. Those plants grow 4' high and at least 5' across. The flowers are smaller, but their summer profusion is a joy to those who drive by.

I have yet to enjoy the luxury of choosing which style I prefer. My problem has always been to get plants to survive. No matter how early I planted, the roots rarely had time to settle before the onset of summer heat and dry air. The few times I did succeed, the green canes were destroyed by the drying winds of February. The only pruning I ever did was removing clearly dead wood.

Four years ago I built a wooden fence about 30' south of the house I hoped would break the wind, at least at ground level. The roses I put in the next spring, 2007, survived, but didn’t do particularly well. There were few flowers in June of 2008, and they tended to be deformed. Then nothing until late summer when a few, more attractive flowers opened fully.

This year began the same, except the transition from too cool to too hot was shorter than usual. Nothing grew anywhere in June, not even the iris or the usual Dr. Huey rootstock. When the monsoons arrived, I began the summer weeding. I got to the roses that grow in the drip line of the south roof the first week of August.

I’d grown tired of the golden hairy asters that were threatening to take over, and removed them. Then, because I had time, I finished laying tiles along the porch edge, a project I’d started years ago to protect the building from rain and hadn’t completed then because I’d run out of materials. Treated tiles had been sitting in the garage for years.

I bought dry fertilizer, and scattered it just as the rains stopped.

Then I began to worry perhaps the asters had acted as natural shelters for the splices where the hybrids joined their root stock. I needn’t have been concerned. At the east end of the house, tomatillos expanded their territory, while barnyard grass moved into the center. Even if they die with the frost, they’ll leave a mulch of dead leaves and a stand of old stalks to divert the winds.

Water continued to drip off the metal roof as moisture pulled from the ground in the day, condensed in the night. By the end of the August, I noticed some new red leaves on the floribundas. Then I saw new canes a foot high around one of the teas. For the past few weeks, for the first time since I’ve had this garden, the red Olympiad has been in full bloom, rivaling the neighboring Betty Prior.

Everything I did breaks the rules I was given as a child, and nothing I did was unusual. I never get around to pruning dead wood or fertilizing until August. Yet, the roses are thriving for the first time.

I wonder why roses, which are supposed to do so well in June, have such a different cycle here in the rio arriba. I can only think many of our perceptions go back to the old roses that came from the Levant, and that the introduction of genes from Chinese roses did more than allow plants to bloom all season. After all those older roses can bloom early because they flower on old stems. The newer hybrids bloom on new wood, which foreshortens their growth cycle.

The new roses we imported in the middle 1700's were originally from places like Yunnan and Sichuan, large provinces in south western China where average summer temperatures are in the 70's. Successful flower production involves both temperature and solar radiation, which is higher in mountainous areas like Yunnan and Sichuan.

When new canes first emerge, they prefer lower air temperatures which encourage photosynthesis. However, the young leaves are still too weak to send nutrients to the flower buds that are developing at the tip. If carbohydrates are not transferred from older leaves, the buds may atrophy.

During the phase when buds are developing, the quality of the light becomes more important than the air temperature. Then, when the buds begin to open, temperature again is important. However, while warm temperatures often produce more colorful and more fragrant flowers, the buds themselves prefer to open when temperatures are cooler, just before dawn. When temperatures rise, they rest until after the next dark period.

Here in the Española valley, when temperatures vary so widely and soil temperatures may remain cool, there’s no time to produce a reserve of older leaves to supply the buds of June. After the monsoons, a long enough period exists for new canes to produce flowers that draw on food from the earlier growth. While those flowers are racing against the seasonal decrease in solar radiation, the decline is less dramatic at 6000' than at sea level.

East of the Mississippi, they have long springs and hot, debilitating summers. Here, we have erratic, often abbreviated springs, and long, cool seasons after the monsoons. Roses bloom when they can, early in the east, late here.

Notes:
Berninger, E. "Development Rate of Young Greenhouse Rose Plants (Rosa hybrida) Rooted from Cuttings in Relation to Temperature and Irradiance," Scientia Horticulturae 58:235-251:1994.

Evans, R. Y. Control of Rose Flower Opening, 1987, cited by Michael S. Reid, "Flower Development: From Bud to Bloom," Acta Horticulturae 669:105- 110:2005.

Khayat, Eli and Naftaly Zieslin. "Effect of Night Temperature on the Activity of Sucrose Phosphate Synthase, Acid Invertase, and Sucrose Synthase in Source and Sink Tissue of Rosa hybrida cv Golden Times," Plant Physioloogy 84:447-449:1987

Ushio, Ayuko, Tadahiko Mae and Amane Makino "Effects of Temperature on Photosynthesis and Plant Growth in the Assimilation Shoots of a Rose," Soil Science and Plant Nutrition 54:253–258:2008.

Photograph: Betty Prior, a single pink floribunda, and Olympiad, a red hybrid tea rose, 16 October 2010.