Sunday, July 08, 2018

Raspberry Flowers


Weather: We were supposed to get rain Thursday night, but of course didn’t. The water went north along both sides of the mountains, but bypassed the valley. The weather bureau claimed temperatures were lower, but 89 is still high, especially when the heat lasts longer in the day. The traveling water vapor did increase the relative humidity so plants didn’t need emergency watering every noon, though some seedlings suffered when I sprayed them less often.

Last useful rain: 6/16. Week’s low: 47 degrees F. Week’s high: 93 degrees F in the shade.

What’s blooming in the area: Hybrid roses, yellow potentilla, desert willow, trumpet creeper, bird of paradise, fern bush, silver lace vine, daylilies, lilies, red hot poker, red-tipped yuccas, Spanish broom, Russian sage, bouncing Bess, hollyhocks, datura, sweet pea, hollyhocks, annual four o’clocks, yellow yarrow, cultivated sunflowers, coreopsis, black-eyed Susan

What’s blooming in my yard: Miniature roses, buddleia, Maltese cross, golden spur columbine, coral beards tongue, large-flowered soapwort, Johnson Blue geranium, catmints, lady bells, sidalcea, winecup mallow, blue flax, tomatillo, pink evening primroses, white-flowered spurge, sea lavender, perennial four o’clock, white yarrow, chocolate flowers, blanket flower, Mönch aster

What’s blooming outside the walls and fences: Tamarix, purple mat flower, stick leaf, white tufted evening primroses, velvetweed, bindweed, silver leaf nightshade, greenleaf five eyes, leather leaf globemallow, scurf pea, alfalfa, white sweet clover, Queen Anne’s lace, Hopi tea, fleabane, horseweed, wild lettuce, common and native dandelions, goat’s beard, plain’s paper flower, golden hairy asters, Tahoka daisy

Bedding plants: Pansies, violas; local petunias

Tasks: I’ve been cleaning the main bed and rescuing plants from invading golden spur columbines, dandelions, and cheat grass. They all but decimated the anthemis and coreopsis. They shaded the plants and kept water from dripping on them, then columbine dropped its seeds between dead stems. I did find a few anthemis seedlings I’m hoping will make it through the summer. They are perennial.

Animal sightings: Rabbit, hummingbirds, goldfinch, other small brown birds, geckos, sidewalk ants, bumble and small bees, hornets, other small flying insects, grasshoppers; heard crickets

The neighbor’s cat seems to come every morning and promenade the yard. I’ve found it many places, usually resting on a concrete block. It no longer runs, but watches me. As soon as I walk away, it disappears. It doesn’t distrust me so much as wants to keep its ways secret. I suspect it goes home when it gets hungry or when the temperatures get so high the air conditioned rooms filled with children and a dog are preferable.


Weekly update: My total fruit harvest so far this year has been eight raspberries and three sour cherries. The birds punctured three sour cherries, which withered away. The frosts took the apricots, peaches, and sweet cherries.

The raspberries were Canbys. The Willamettes I mentioned in a 2007 post died out during the winter of 2014-2015, and this was what I found in the local store. One Missouri nursery dropped the cultivar because canes are killed in "late season cold" snaps and it "performs rather poorly on clay soil." [1]

Not exactly ideal for northern New Mexico, but my requirements were a bit different. Beyond surviving and producing fruit, the most important attribute was that the flowers and fruit appeared early. The canes don’t like heat, [2] and if the critical period for fruit development occurs after the heat sets in, the berries don’t develop. I’m still digging out some Heritage because the late summer variety only produced tiny berries that attracted hornets. [3]

This was the first time I noticed the flowers. The petals begin falling the day after they open, [4] and when I was working my schedule probably did not synch with theirs. Just as important is the fact the five-petaled white flowers hang below the leaves where they aren’t particularly visible.

When the petals fall they leave a fringe of white male stamens with dark anthers at the end. Inside, are slender female threads. Many researchers believed the two met on their own and fertilization occurred even before the flowers opened. [5]

Many nursery catalogs claimed raspberries were self-fruitful. They weren’t attempting to be botanically correct. They only wanted to assure potential buyers they didn’t need to plant several varieties like they would apples.

Other researchers tested the autogamous theory and found, if bees were kept from the canes, the berries contained fewer segments. The core receptacle that would develop inside the hollow berries contained the nectar that attracted them. [6]

I realized that structurally a raspberry was more like an ear of corn than it was a stone fruit of which it was a subclass. Those inner threads were like the silk. Each led back to an ovary that developed into a berry segment or a corn kernel. The ones were attached to a white cone and the others to a cob. When I looked carefully at one of the berries I even saw some vestigial threads that hadn’t been pollinated.

Technically, of course, raspberries are drupes or stone fruits. Only, instead of a single pit like a peach, the stone is a grain embedded in an individual drupelet. The exterior is hairy, so when I ate the fruits I had three sensations: the sweetness of the mesocarp surrounding the pit, the fuzzy duskiness of the skin, and the grittiness of the stone.


Notes on photographs:
1. Canby raspberry (Rubus idaeus) flowers, 24 May 2018.

2. Canby raspberry flower after the petals fell and the sepals remained, 24 May 2018.

3. Canby raspberry fruit 35 days later, 30 June 2018.

End notes:
1. "Raspberry Varieties We Have Grown." Lakeview Farms website.

2. Marvin P. Pritts. "From Plant to Plate: How Can We Redesign Rubus and Ribes Production Systems to Meet Future Expectations?" International Society for Horticultural Science. International Rubus and Ribes Symposium, Dundee, Scotland. 30 September 2002.

3. Lakeview Farms also stopped selling Heritage because of "its slightly smaller size, attractiveness to stinging insects, and moderate prickerish canes. It is prone to sunburn injury and must be irrigated intermittently if the temperature gets hot enough." It’s the only variety being sold in this area. The Canbys were a fluke, and haven’t appeared since.

4. S. E. McGregor. "Raspberries." In chapter 7, "Small Fruits and Brambles" of Insect Pollination of Cultivated Crop Plants. U. S. Department of Agriculture. Agricultural Research Service. 1976.

5. McGregor.
6. McGregor.

No comments: