Cold weather, snow, thinking about nematodes

We won't starve or get scurvy! Plenty of food in the hoophouse!  Credit Twin Oaks Community
We won’t starve or get scurvy! Plenty of food in the hoophouse!
Credit Twin Oaks Community

This morning we have about 6 inches of snow. Knowing it was coming, we stocked the kitchen with extra potatoes from the root cellar (for those who don’t know, it’s next to impossible to pull a loaded garden cart through loose snow). We also braved the begiinning of the snow yesterday afternoon to harvest some spinach outdoors. We did try digging leeks, but the ground was frozen too deep. If the weather forecast holds true, we won’t see the soil for a week, as not much thawing is predicted. But the hoophouse will feed us. One winter the outdoor crops were inaccessible due to snow, ice or freezing weather, for a whole month, and we were able to feed 100 people in salads and cooking greens from the hoophouse. That wasn’t typical central Virginia weather. But typical isn’t typical any more.

Young blueberry bush in the snow. Credit Bridget Aleshire
Young blueberry bush in the snow.
Credit Bridget Aleshire

Our hoop house is a 30 x 96 ft Clearspan Gothic Cold Frame type from Farmtek. We made ours with bows four feet apart for better strength against ice and snow build up, and the gothic arch shape helps shed snow, as does the rigidity provided by having two layers of plastic and an air bubble. A couple of years ago when we were changing the plastic we added some reinforcement props to the west wall, which was leaning in from the force of winds. On Sunday night I was very glad of that, because we had very high gusty winds, and I lay in bed trying to ignore the sound of the wind, imaging we would lose our hoophouse. Imagine my relief to wake up to see it still in place!

We did have a big pine tree come down near our dining hall, but it missed the big propane tanks and didn’t even block the road by the Tofu Factory. We didn’t lose electric power either, so we have been lucky in several ways. Now I am watching the forecast for Thursday night. At one point the forecast was for a low of -9F, which is unthinkably low! Even the Vates kale won’t survive that – unless we have snow covering, which we still might! Currently the forecast has “warmed” to -2F. We always subtract 5F from the Louisa forecast, because it is often that much colder here.


Meanwhile, here are some warming photos from Hawai’i. Following my article in Growing for Market about dealing with nematodes in the hoophouse, I heard from Gerry Ross at Kupa’a Farms on Maui, at  2000 feet above sea level. (Take a look at their beautiful website, and feel the sunshine!) Root Knot Nematodes are a warm weather problem – they are inactive if the soil is colder than 50F. We had never seen their damage until a few years ago. In warmer climates they may have to deal with them constantly. On Maui the soil temperatures never go below 59F! Their high tunnel is for insect exclusion, not warmer temperatures, so it is covered with insect mesh, not polyethylene.

Nematode-susceptible food crops. Credit Gerry Ross, Kupa'a farms
Nematode-susceptible food crops.
Credit Gerry Ross, Kupa’a farms

Gerry wrote that he is trying a hoophouse crop rotation: “We started with cukes, tomatoes, zukes, and peppers for the hotter summer weather. We then moved to sunn hemp-Piper sudan cover crop for about 45 days, and then to a winter rotation of brassicas with peas and cukes. We will mow and disc the brassicas down in about a month when it starts to get on the warm side and harvest is over and plant directly into the debris with peppers, tomatoes and cukes/zukes. So far we are really pleased with the results…..the brassicas are really clean with no cabbage moth damage. This is just one way to manage the RKN I suspect but so far so good.”

Nematode -fighting cover crops. Credit Gerry Ross, Kupa'a Farms
Nematode -fighting cover crops.
Credit Gerry Ross, Kupa’a Farms

Outdoors, for field crops, Gerry said:

” we usually do 2-4 month cover crop like sunn hemp and Piper sudan grass and then follow that with our most susceptible crops (potatoes, carrots, beans, beets). When those come out we follow with brassicas, lettuce, onions. We usually grow row crops for 8 months in a field and then do a cover crop. The sunn hemp we use is called “Tropic Sunn” and the USDA on Molokai has developed it and bred the alkaloids out of it. Not sure it is widely available but try http://oahurcd.org/ and see if they will mail it to you. We also use vetch as a cover but it can get whacked with RKN so we co-plant with a scaffolding nonhost like the Piper sudan or oats.”

Brassicas in nematode-fighting hoophouse crop rotation. Credit Gerry Ross, Kupa'a Farms
Brassicas in nematode-fighting hoophouse crop rotation.
Credit Gerry Ross, Kupa’a Farms

“Buried in some of the research by the sugar cane companies was a comment that molasses seems to drive down populations of RKN in the soil. We found application of local molasses to be difficult because it is so thick and viscous and hard to make spreadable BUT a local farming store did get us some dried molasses which is used as a horse supplement in the Mainland and applying that to the soil seemed to really help. That might be something you could try.

We have tried lots of compost (food-waste based as manure is not easily available here) and have created beds with loads of earthworms but the RKN persists.
We have found that some lima beans perform well even with heavy RKN infestation esp the Florida speckled butterbeans (huge purple speckled beans on wild vines that live for three years here!) and Fordhook that seem to just carry on regardless of RKN infestation. Fava beans on the other hand suffer mightily and do not produce at all. 
Thank you for the list of remedies and resistant cultivars. We have used the NemaQ and it seems to work if we run through our drip lines or water it in in diluted form in our raised beds. We might try grafted tomatoes too because one of the available rootstocks is RKN resistant. “

So, here I sit with “good garden planning weather” and fight my desire to just hibernate till it warms up!
Field manual Vabf unnamed