Climate change and pest control

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I recently learned some more about online weather tools for farmers from Eric and Joanna Reuter in Growing for Market. The National Weather Center Climate Prediction Center (CPC) has a wealth of useful info. From the “WPC 7-day QPF” map above (Weather Prediction Center 7 day quantitative precipitation forecast) I see we could get up to an inch of rain over the coming week in central Virginia. Other maps on the site show we can expect above normal temperatures and rainfall for the first week of January. (I’m saying rain, because with above normal temperatures, the precipitation won’t be snow.)

There are maps with forecast conditions for the next month, the next three months and even the whole of 2018, although of course the more intervening time means more chance of things changing before we get there.There is a detailed discussion explaining “La Niña conditions are present, with a transition to ENSO-neutral favored during January-March 2017.” The report was written in November, predicting weak La Nina conditions continuing through March 2017.

Winter offers a good opportunity to explore these tools and get familiar with them (the abbreviations and technical language do take a bit of getting used to). If I were to open this site in mid-summer when already very busy, I think I would struggle to sit still long enough to absorb the information. By figuring it out at the slow time of year, I’ll be more ready to dip in and take advantage of timely info in the main growing season.

If the embedding has worked out right, here is a “Climograph” for Louisa County, Virginia:

<iframe frameborder=”0″ width=”470px” height=”430px” style=”overflow:hidden;” scrolling=”no” src=”http://www.usclimatedata.com/climate-graph.php?id=usva0445&system=american&title=1″></iframe>

And if it didn’t embed, here’s the link: http://www.usclimatedata.com/climate/louisa/virginia/united-states/usva0445/2015/2

december-beds-with-row-cover-wren
Outdoors in December – rowcover everywhere! Photo by Wren Vile
Hoophouse beds in December. This is why we have a hoophouse! Photo Wren Vile
Hoophouse beds in December. This is why we have a hoophouse!
Photo Wren Vile

This week I also read an interesting article by Rebekah L Fraser in Growing magazine on the Push-Pull Method of pest control, which was developed in Kenya. In Kenya this method is used to protect crops from both invasive weeds and insect pests. Some plants can suppress others by selective allelopathy. Tick-trefoil not only suppresses some weeds but also repels pests, while conserving the soil in the process, and providing stock feed or green manure when cut. Plus, as a legume, the tick-trefoil fixes atmospheric nitrogen (which feeds the next crop) and reduces greenhouse gases (which helps save us all). This is the “push” half of the combination. Tick-trefoil interplanted with corn repels weeds and pests.

Push-pull pest control
Push-pull pest control

The “pull” half involves Napier grass as an attractive trap crop for corn borers. This trap crop is planted as a border around the corn patch. The female stem-borers are repelled by the tick-trefoil out of the corn to the border where they lay eggs on the Napier grass. It’s sticky exudates and sharp silica hairs kill the stem borer larvae when they hatch. Read more on www.push-pull.net .

It’s so heartening to read about organic sustainable ways farmers in sub-Saharan Africa are working to end hunger and poverty. And these principles can surely be applied to other crops in other regions.

Not much gardening happening; videos, events, articles

A Chandler blueberry layered in a pot. Photo Kathryn Simmons
A Chandler blueberry layered in a pot.
Photo Kathryn Simmons

Not much gardening has been happening here. The soil is still saturated, so we can’t till or plant. We have spread a lot of compost on lots of raised beds. We have finished our blueberry pruning and are looking at filling the gaps before the buds break. We have 44 old blueberry bushes in one planting and 20 younger ones in another spot. All the 20 younger ones are alive, but there are about 8 gaps in the older patch. We propagate our own blueberry plants for gap-filling, by layering.

This involves taking a healthy low-lying branch and pinning it down into some soil. Before pinning it, we scrape the lower bark off where it touches the soil, to help the branch grow roots from that point. We used to pin the branches down into pots of soil, as in the photo above, but for the past few years we have simply been pinning them into the ground. This has the advantage of reducing the chance of the roots drying out (they are in a much larger volume of soil). But it has the disadvantage of being harder to see and so more likely to get damaged, mulched over or uprooted by our visitor-helpers. We use 6″ sod staples, those wire staples sometimes sold to hold down geotextiles or row cover or drip tape. We tie a long piece of bright colored plastic flagging tape around the top of the staple to make it easier to see. If the branch tries to spring out of the soil, we use rocks to hold the staple down. With the pot system, we would cut the new plant from the mother once it seemed to have life of its own. Now we grow them in the soil and we have simplified our system so we pin down new layers while we are doing the pruning, and leave them for a whole year.

After the pruning we dig up the previous year’s layers and replant them. We label and flag them, and even put wire netting cages round them for protection. And then water twice a week if nature doesn’t, for a few weeks, then once a week for the summer.

Young blueberry plant protected with wire netting. Photo Kathryn Simmons
Young blueberry plant protected with wire netting.
Photo Kathryn Simmons

We keep maps of which blueberry varieties are where in our patches and during the harvest season we flag the most tasty ones, so we know where to go to propagate more.


The Virginia Beginning Farmer and Rancher Coalition is starting a video series with five participating farms. The first video, from Bellair Farm, 11 miles south of Charlottesville, can be seen here:

A different farm will release a YouTube video each week. The other four farms are
Porcello Farm (Charlottesville)
Agriberry Farm (Hanover)
Amy’s Garden (Charles City)
Browntown Farms (Warfield)

The farms address how they got started, where they sell their products, how they organize their labor, and lots more. The conversations were recorded to create these videos to help people learn more about Virginia’s farmers as well as gather practical information to use on your own farm. The goal of the Virginia Beginning Farmer and Rancher Coalition is to support new farmers at any scale, particularly historically under-served groups.


culpeperimage-front-coverComing right up is my talk at Culpeper County Library next Sunday 2/28 from 2-4pm in their meeting room. I’ll be chatting about writing my book, answering gardening questions, discussing the importance of local sustainably grown food, and selling and signing copies of my book.


The Virginia Berry Production and Marketing Conference
(North American Raspberry and Blackberry Association’s Annual Conference) will be in
Williamsburg, VA – March 1-4, 2016. I haven’t yet got any info I can paste in, but click on the link and find details and registration form.


Growing magazine has just arrived and I’m interested to see they have several articles about carrots. Good carrot production, how to produce consistent carrots twice a year (in central California), insect-infested carrots and weeds in carrots. Why carrots only twice a year? We plant carrots in February, March, April, May and August. Sometimes even in June and July if we need to. There’s also an article about soils and climate change. Growing is not an organic magazine, so I pick and choose from their advice. It is what I’d call open-minded about organics: they recognize some growers use organic methods and they want their magazine to be read by those farmers too. Some articles are online. Subscription to the magazine is free (I imagine the advertisers cover the costs)

Carrot photo from Small Farm Central
Carrot photo from Small Farm Central