- Monday, July 29, 2013
The following article is from a blog called Deb's Garden written by Deborah Elliot. You can subscribe to her blog by going to this link: http://debsgarden.squarespace.com/
The doldrums have arrived. Gardening is at a minimum. I prefer to be inside, reading my newest garden magazine. Outside, plants may be loosing their vigor with bright green leaves fading to pale blueish gray, leaf edges crinkled, leaves dropping — all signs of heat stress. Meanwhile, bugs select the weakened plants for midsummer's wildest party, sucking and munching and having an orgy with all their friends and relatives. What's a gardener to do?heat stressed leaves
Don't let the doldrums get you down! Here are ten things one can do to summer proof the garden:
1. Choose the right plants. Many ornamental plants now have heat zone recommendations as well as hardiness zones listed on their tags. Developed by the American Horticultural Society in the late 1990s, the heat zone map identifies 12 heat zones in the US. These heat zones are based upon how many days a year the temperature rises above 86 degrees, the temperature when plant cells begin to deteriorate. I am in heat zone 8, which means there are 91-120 days when temperatures rise above 86. Look to see if a tag has two ratings for a given plant, such as 3-7/4-6. The first set of numbers indicates the plant is winter hardy in hardiness zones 3-7, and the second set of numbers indicates the plant will survive summers in heat zones 4 through 6. Remember the hardiness and heat zone maps are two different maps, so one needs to know both zones for one's location. I am on the edge of hardiness zones 7b/8a, but I am firmly in the middle of heat zone 8. There are plenty of plants that can take my winters but not my summers! Replace plants that die with others that are more likely to survive. Native plants are usually reliable, because they are well adapted to both winter and summer conditions.
- Tuesday, March 12, 2013
Study Shows That Bees and Flowers Communicate Using Electrical Fields
February 22, 2013 by Staff
Various flowers (Left: Geranium magnificum; Middle: Gerbera hybrida; Right: Clematis armandii) showing a composite of immediately before and after application of charged powder paint. The pattern of powder deposition reveals the shape of the electric field. Image by Dominic Clarke and Daniel Robert
Scientists from the University of Bristol have discovered that flowers use patterns of electrical signals in concert with the flower’s other attractive signals to enhance floral attraction to insect pollinators such as bumblebees.
Flowers’ methods of communicating are at least as sophisticated as any devised by an advertising agency, according to a new study, published today in Science Express by researchers from the University of Bristol. However, for any advert to be successful, it has to reach, and be perceived by, its target audience. The research shows for the first time that pollinators such as bumblebees are able to find and distinguish electric signals given out by flowers.
Flowers often produce bright colors, patterns and enticing fragrances to attract their pollinators. Researchers at Bristol’s School of Biological Sciences, led by Professor Daniel Robert, found that flowers also have their equivalent of a neon sign – patterns of electrical signals that can communicate information to the insect pollinator. These electrical signals can work in concert with the flower’s other attractive signals and enhance floral advertising power.
Plants are usually charged negatively and emit weak electric fields. On their side, bees acquire a positive charge as they fly through the air. No spark is produced as a charged bee approaches a charged flower, but a small electric force builds up that can potentially convey information.
By placing electrodes in the stems of petunias, the researchers showed that when a bee lands, the flower’s potential changes and remains so for several minutes. Could this be a way by which flowers tell bees another bee has recently been visiting? To their surprise, the researchers discovered that bumblebees can detect and distinguish between different floral electric fields.
Also, the researchers found that when bees were given a learning test, they were faster at learning the difference between two colors when electric signals were also available.
How then do bees detect electric fields? This is not yet known, although the researchers speculate that hairy bumblebees bristle up under the electrostatic force, just like one’s hair in front of an old television screen.
The discovery of such electric detection has opened up a whole new understanding of insect perception and flower communication.
Dr Heather Whitney, a co-author of the study said: “This novel communication channel reveals how flowers can potentially inform their pollinators about the honest status of their precious nectar and pollen reserves.”
Professor Robert said: “The last thing a flower wants is to attract a bee and then fail to provide nectar: a lesson in honest advertising since bees are good learners and would soon lose interest in such an unrewarding flower.
“The co-evolution between flowers and bees has a long and beneficial history, so perhaps it’s not entirely surprising that we are still discovering today how remarkably sophisticated their communication is.”
The research was supported by the Leverhulme Trust.
Publication: Dominic Clarke, Heather Whitney, Gregory Sutton and Daniel Robert, “Detection and Learning of Floral Electric Fields by Bumblebees,” Science DOI: 10.1126/science.1230883
Source: University of Bristol
Image: Dominic Clarke and Daniel Robert
- Sunday, January 13, 2013
The Essential Seed-Starting Timetable
Thank you for having signed up for horticultural emails from Kitchen Garden Seeds, Van Engelen and John Scheepers*. Pictured from top to bottom: Quadrato d'Asti Bell Peppers, Milano Plum Tomatoes, Magenta Sunset Swiss Chard and Heavenly Blue Morning Glories.
Did you ever wonder why certain varieties of seed are started indoors? It is usually because the days to mature harvest exceed the amount of time between your spring Frost-Free Date and your first fall frost. By starting these varieties indoors in advance, you get a four to 14 week jump-start on the development of seedlings. Other varieties like to be started indoors so that you can really pamper them with consistent moisture and warmer temperatures. Real warmth-lovers, like Eggplants, Peppers and Tomatoes, like to be coddled with 24-7 grow lights until they are 'toddler' seedlings when they can start to handle cooler, dark nights.
Here is the general Seed-Starting Schedule for seeds that should be started eight weeks before your Frost-Free Date in your Horticultural Zone.
Horticultural Zones 9 & 10: Start seeds indoors in early to mid January.
Horticultural Zone 8: Start seeds indoors in early February.
Horticultural Zone 7: Start seeds indoors in mid February.
Horticultural Zone 6: Start seeds indoors in late February.
Horticultural Zone 5: Start seeds indoors in early March.
Horticultural Zones 1-4: Start seeds indoors in mid to late March.
Here is the seed-starting schedule by variety and the number of weeks before your Frost-Free Date.
Four Weeks: Bitter Melon and Cucuzzi Edible Gourds.
Six Weeks: Asparagus, Basil, Echinacea Root, Fennel (herb and vegetable), Melons, Okra, Onions, Rhubarb and Shallots.
Eight Weeks: Amaranth, Anise Hyssop, Bell Peppers, Catnip, Chile Peppers, Chives, Lovage, Marjoram, Oregano, Paprika Peppers, Parsley, Sage, Savory, Sweet Peppers, St. John's Wort, Thyme, Tomatillos and Tomatoes.
Nine Weeks: Broccoli, Cabbage and Kohlrabi (transplant out four weeks before the last frost date).
Ten Weeks: Eggplant, Jicama, Lavender and Lemongrass.
Eleven Weeks: Artichokes, Cauliflower and Leeks (transplant out four weeks before the last frost date).
Twelve Weeks: Brussels Sprouts, Cardoons, Celeriac, Celery, Cutting Celery, Parsley Root and Stevia.
Sixteen Weeks: Rosemary and Strawberries (for first year crop).
These beautiful varieties prefer to be started indoors prior to transplanting out after your Frost-Free Date.
Two Weeks: Baptisia.
Four Weeks: Celosia.
Five Weeks: Alyssum.
Six Weeks: Dahlias and Echinacea.
Eight Weeks: Alternanthera, Amaranth, Baby's Breath, Balsam, Black-eyed Susans, Cutting Ageratum, Canterbury Bells, Catmint Nepeta, China Asters, Cleome, Coleus, Coreopsis, Euphorbia, Forget-Me-Nots, Gaillardia, Globe Amaranth, Hardshell Gourds, Helichrysum Strawflower, Heuchera, Milkweed, Nicotiana, Nigella, Platycodon, Scabiosa, Snapdragons, Statice, Stock, Thunbergia, Tithonia and Yarrow.
Ten Weeks: Hibiscus, Phlox and Victoria Salvia.
Twelve Weeks: Datura, Dianthus, Digitalis, Helichrysum Silver Mist, Heliotrope, Hollyhocks, Johnny Jumpups, Lobelia, Salvia and Viola.
Fourteen Weeks: Verbena.
Midsummer for Fall Use: Ornamental Kale.
The second part of your order should include varieties that prefer to be direct-sown easily into the garden after your Frost-Free Date. These are the vegetables and herbs that magically come to life after you gently nudge them into the warming spring soil for abundant reward: Arugula, Asian Greens, Beans, Beets, Belgian Endive, Borage, Broccoli Raab, Brown Mustard Seed, Carrots, Chamomile, Swiss Chard, Chervil, Chicories, Chinese Broccoli, Chinese Cabbage, Claytonia, Collard Greens, Coriander, Corn, Cress, Cucumbers, Daikon Radishes, Dandelion Greens, Dill, Edamame, Endive, Escarole, Fava Beans, Fennel, Kale, Kohlrabi, Lemon Balm, Lettuce, Lima Beans, Mache, Melons, Minutina, Mizuna, Mustard Greens, Orach, Pak choi, Parsnips, Peas, Pea Pods, Pumpkins, Radicchio, Radishes, Rutabagas, Salad Greens, Salsify, Shelling Beans, Shiso, Snap Peas, Sorrel, Spearmint, Spinach, Summer Squash, Winter Squash, Turnip Greens and Turnips.
- Friday, January 11, 2013
Hey GDOGC Members!!
Have you read a good gardening book lately? YOU HAVE!! Would you like to tell us about it? Write a review and send it to me so we can post it on the blog or in the newsletter. Email me, the GDOGC Webgoddess via the "Contact Us" page.