We can all identify with how time flies. The longest day or summer solstice for this year is now long gone. Little by little, daylight is sneaking away and shall continue to do so until just before next Christmas when we have our shortest day.
Speaking of “sneaking,” let me put a question to you. Have you ever snuck a potato or two by inserting a hand into a potato plant hill early in the season to check out the size of forming tubers? Someone I know who sells early-maturing potato varieties does it regularly. Something tells me this page could be devoted mostly to spuds. Hope you’re OK with that ’cause next to fruits of the vine, “apples of the earth” continue to generate a lot of interest among home gardeners. By the way, I’ll also touch briefly on strawberries.
This is where the garden train stops long enough for gardeners to get on board and toot their own horn, blow their own whistle and have a right to brag about their gardens. A tip of my hat means howdy do! You’re all as welcome as hummingbirds, house wrens and hollyhocks.
Followup to sangre potato
Received the following in my inbox: “Re: the May 17-16 Grainews. The problem with the Sangre potatoes is tuber flea beetles. These flea beetles feed on the new potato growth and the larvae migrate into the new potatoes. Control: Sevin insecticide at spud emergence, floating cloth, grow potatoes well away from the old site. This problem is very common in Alberta.” Dr. Ieuan R. Evans 780-987-4398, former Alberta provincial plant pathologist.
I, Ted, followed up with a telephone call to Dr. Evans and we had an in-depth conversation about flea beetles. I learned they are a diverse group.
The pest known as solanaceous flea beetles is also called tuber flea beetles. They attack potatoes, tomatoes, peppers and sometimes beans, according to Dr. Evans. This beetle is the most serious insect pest of potatoes in B.C. More recently they’ve been found in Alberta and appear to be moving eastward. Flea beetles are highly mobile making control a challenge. Adults of this species primarily feed on potato leaves, and inflict injury by giving them a shot-holed appearance. The larvae inflict the main damage by feeding on the tubers causing pimples, surface channels, and shallow networks of fine tunnels. Vacant tunnels are lined with brown, corky skin and can be removed by deeper peeling. This leads to annoyance and waste, plus obvious reduction in marketability of potatoes.
Dr. Evans points out that “canola flea beetles, cabbage flea beetles and potato flea beetles are all very different. Potato flea beetles begin eating leaves as soon as plants emerge, later moving to potato stems where their eggs are deposited. “Hatched maggots move down the stems and burrow into developing tubers where they feed and make those little funny feeding channel marks. Later, maggots pupate and emerge as adult beetles usually in August, remaining in the soil over winter. The following year beetles surface when temperature is right and attack newly planted potatoes again.”
For controls Dr. Evans suggests “spraying potato plants once or twice early on with Sevin or Ambush available at garden supply stores. Otherwise you’ll have to cover them with horticultural cloth from time of planting until about the end of June or let remain all season if desired.” Dr. Evans places similar floating row cover cloth over broccoli, cabbages and cauliflower with absolutely excellent defence against flea beetles that attack them.
Thanks to Dr. Ieuan R. Evans and many others out there in Grainews reader land who take time to email, write and phone. You’re all distinguished in my book. What I like about Grainews and books is the printed page is always there.
Crop protection cloth
Lightweight and heavyweight row cover barrier cloth does a good job at foiling insect pests such as flea beetles, thrips, aphids, cabbage moth worms, maggot flies, leaf miner flies, carrot rust flies and many others. The material insulates crops from frost and provides shade from sun, allows misty entry of rainfall and provides moisture retention.
Floating row cover is reusable and can be stored out of season for future use. It’s available at some garden centres or contact the following:
- West Coast Seeds
Delta, B.C., V4K 3N2
phone toll free 1-888-804-8820
or visit westcoastseeds.com
- Natural Insect Control
3737 Netherby Rd.,
Stevensville, Ont., L0S 1S0
phone toll free 1-866-926-2904
or visit naturalinsectcontrol.com
Among other additional alternative controls NIC also sells live beneficial insects, traps, lures, barriers, bat and purple martin houses.
Tarnished plant bug
Early on before flowering begins cover strawberry plants with floating row cloth (described earlier). This halts or impedes entry of the tarnished plant bug (Lygus). Both the adults and their nymphs inflict damage by feeding and sucking sap from all parts of strawberry plants including blossoms. Embryos within seeds on forming fruit are destroyed preventing proper fruit tissue growth. Affected strawberries take on a stunted, malformed cat-faced appearance that’s hard like a button. Tarnished plant bugs are winged weevils capable of flying about and spend winter above ground in plant debris under snow and in hedgerows. These pests can be a major concern in commercial strawberry production.
Ted’s personal research notes
Let me ask: Did any home potato growers add onion skins at time of planting? If yes, I’d appreciate your feedback. This year from a personal perspective I, Ted, placed a handful of mixed dried skins from yellow, white and purple onions beneath each seed potato planted in over 100 holes with one exception. This did not include a baker’s dozen of a purple-flesh variety that was planted without onion skins. From among 100 onion skin-treated plants I’ve hand-picked less than two dozen adult potato beetles and one cluster of eggs up to this point (June 24-16). Of course it’s still early in the season and weather has certainly fluctuated a lot and left its mark. I’m not jumping to any conclusions just yet as to whether adding dried onion skins at planting time makes any difference. By contrast, the aforesaid purple-fleshed potato variety planted without onion skins had many more adult potato beetles and hatched potato bugs. This is unscientific of course, but since I’m my own backyard scientist I shall pursue this further by experimenting again next season. Meanwhile I’m now saving more dried onion skins.
Most gardeners have heard of essential oils. Scientists in Turkey have been testing control of potato bugs without pesticides using essential oils. So far, Turkish researchers have found that essential oils of oregano, thyme, wormwood and yarrow are toxic to adult potato beetles. Concentrations ranged between 10 to 20 ml of essential oil mixed separately with one litre of water and applied as a spray (20 ml equals about four Canadian teaspoonsful). At lower concentrations than indicated, each separate preparation repelled some adult beetles and fewer larvae emerged from their eggs. Effectiveness began to appear between six to 24 hours depending on which oil and how much was used. This is a chance to do some backyard experimenting if you so choose and enjoy being your own at-home garden scientist.
Researchers didn’t assess whether beneficial soil organisms were impacted in any way by use of aforementioned essential oil sprays, or if harvested potatoes acquired a different seasonal flavour. Essential oils are available at health food and specialty stores and prices vary depending on selection.
It’s long been known that many herbs are beneficial to the well-being of humans. Herbs also attract pollinators and repel insect pests. Seeding oregano and thyme by your potato plants may also help repel beetles.