Tag: wheelhoe

Colorado potato beetles, germinating lettuce, wheelhoes

A ladybug on a potato leaf, looking for pests to eat Photo Kathryn Simmons
Not a Colorado potato beetle: A ladybug on a potato leaf, looking for pests to eat
Photo Kathryn Simmons

Our spring-planted potatoes are just starting to flower, and I’m now in my weekly routine of monitoring for Colorado potato beetles. I walk the length of the patch and back, switching rows every 9 paces or so. I squish and count the adult CPB, and also count the larvae (I don’t always squish all of those). Did you know you can tell a squashed female CPB from a squashed male? The females are full of orange eggs, until you squash them, that is, then the orange eggs are all over your fingers!

Potato plants can tolerate 30-40% defoliation early in life, 10-60% defoliation during middle age, and up to 100% defoliation at the end of the season without reducing the yield.So don’t panic! But do pay attention. The Action Level for Colorado potato beetle is 1 adult per plant, and that for larvae is 2 per plant. Our rows are 265 ft this year, and the plants are 12″ apart, so I’m looking at 530 plants when I go down and back. So far, we’re doing great. Last week I found 12 adults. This week I found 5 adults and 41 larvae. I still don’t need a mass slaughter program. If we need to spray I’ll use Spinosad. For home gardens you can buy Monterey Garden Insect Spray from Seven Springs Farm in Virginia. Or elsewhere. It is OMRI approved but is very toxic to bees (and Eastern Oysters, should you need to know), so we only spray Spinosad at dusk when the bees have gone home, and make sure not to pour the rinse water from the sprayer into the drains (which go via our septic system into the creek). Generally I use the driveway as a large inert area to spread the wash water over.

But I only use Spinosad if we have to. Another part of my plan is timely mowing of the clover patch next to the potatoes. The clover mix was undersown in the fall broccoli last year, and in the spring we simply bush hog that patch every time the weeds are getting too successful compared to the clover. Or ideally, before that happens. We had flowering crimson clover there earlier, and mowed that. Now what we see is white clover. there is red in the mix too, but I haven’t seen that flowering yet. Our hope/plan is that when we mow the clovers, many of the beneficial insects move over to the potato patch and eat the CPB.

At the great link I gave earlier, Andrei Alyokhin provides good information on the life cycle of the CPB, lots of resources, and a lovely collection of Colorado potato beetle haiku (traditional Japanese poetry) written and illustrated by Mrs. O’Malley’s second-grade students from the Old Town Elementary School in 2008 or so, somewhere in Maine I think. The poetry gives new perspectives as we walk the rows searching for the wee beasties.

Germinating lettuce seed

Some weeks I wonder what to blog about. This week I was helped by a neighboring grower who asked me questions about how I germinate lettuce. Aha! A timely topic! We try to grow lettuce for harvest all year round, here in central Virginia, and exactly how we do that varies with the season.
New flats of lettuce seedlings Credit Kathryn Simmons
New flats of lettuce seedlings
Credit Kathryn Simmons

From January until mid-March I sow in flats in the greenhouse, with heating to get the seeds germinated, then good old solar energy to grow them to transplanting size.

From mid-March to the end of April I sow in flats in the greenhouse, without extra heat.
Spring lettuce bed. Photo Wren Vile
Spring lettuce bed.
Photo Wren Vile

From May to late September I use an outdoor nursery seedbed and do bare-root transplants (heat-tolerant varieties). The soil temperature does not vary as much as the air temperature, so I don’t worry about cool nights.

From June I put shade-cloth over the lettuce seedbed, and only sow in the evening.
In July and August I put ice on top of the newly sown rows, under the shade-cloth.
baby lettuce mix in the hoophouse. Photo Twin Oaks COmmunity
Baby lettuce mix in the hoophouse.
Photo Twin Oaks Community

After that I sow lettuce mix in the hoophouse. (Click the link to see my Hoophouse in Fall and Winter slideshow.)

New Seed-Starters Handbook

Knotts handbook
Knotts handbook

There’s a chart of germination at various temperatures in Nancy Bubel’s New Seed Starter’s Handbook and in the Knott’s Handbook for Vegetable Growers which is all online.The soil temperature range for germination of lettuce seeds is 35-85F, with 40-80F being the optimum range and 75F the ideal soil temperature. At 41F (5C) lettuce takes 15 days to germinate; at 50F (10C) it takes 7 days; at 59F (15C) it takes 4 days; at 68F (20C) only about 2.5 days; at 77F (25C) 2.2 days. Then time to germination increases: 2.6 days at 86F (30C); after that it’s too hot.

A soil thermometer soon pays for itself and saves lost crops and frustration. If it’s too hot, find a cooler place (put a seeded flat in a plastic bag in the fridge or on the concrete floor in the basement). Or cool down a small part of the world. That’s what I do when I sow in the evening, water with freshly drawn cold water, line up ice cubes along the seed rows, and cover with shade cloth.
And finally, to a tool we use a lot at this time of year (when the weather is dry enough for hoeing to be successful): our Valley Oak Wheel Hoes. We have two, both with pneumatic tires (rocky soil jars your wrists, think long-term). We have one with the standard 8″ blade and one with a 10″ blade. We use them for the aisles in our raised beds, for between rows of corn, anywhere without mulch. They are very energy efficient, compared to a hand hoe. And some of the crew treat he opportunity to wheel hoe as a chance for an aerobic workout. Others use a more moderate speed.Cover more ground with less effort, and hence, get more done before the weeds get too big to hoe.
The handlebar height is readily adjustable, the blade assemblies can easily be switched from one tool to another (buy one wheelhoe and several different width blades), there are other attachments such as  a small furrower, a one-sided hiller and a 3-tine cultivator. And there are plenty of replacement parts available: we just ordered spare blades after wearing ours down to narrow strips.9_zoom_1413981475

 

Good news – great hoeing weather! Bad news – more nematodes in the hoophouse

Fall broccoli last year. Credit Ezra Freeman
Fall broccoli last year.
Credit Ezra Freeman

Last week I wrote about transplanting cabbage and sowing kale. We were having “great transplanting weather”, that is, it rained a lot! We filled all the gaps in all 12 rows of broccoli and cabbage in a single hour with four people. There weren’t many gaps, happily. That’s about 1400 broccoli plants and 700 cabbages, our usual amount to feed a hundred people.

This week in the garden, it’s about three weeks since we started the transplanting, so the first rows are ready to be uncovered and hoed. Happily, we now have great hoeing weather! No rain in sight for a week. Central Virginia weather is very variable, and our particular spot is drier than the surrounding area, so if the forecast says 30% chance of rain or less, we are very unlikely to get any. There’s currently a forecast with a 50% chance of rain in 6 days (Monday night). If we can get all the hoeing done, and till or wheelhoe between the rows, then I can broadcast a clover mix and welcome some rain! We like the wheel hoe if the weeds are not too big and not too grassy. The first few rows were quite grassy, so we used our BCS 732 tiller from Earth Tools.

We cultivate around the brassica plants, then broadcast a mix of clovers: 1 oz crimson clover, 1 oz large white Ladino clover and 2 oz common red clover (medium, multi-cut) per 100 square feet. Then if it doesn’t rain, we water like crazy for a few days, which is all it takes to get the clover germinated. We have drip tape for the brassicas, but we need overhead sprinklers for the clover mix. The crimson clover is the fastest growing in the fall, and the others gradually take over in the spring and summer of the next year. We like watching the progression from crimson clover to red to white as each type comes into its strength.

This method of undersowing clovers in fall brassicas works well for us. It provides cover for the soil, legumes which provide nitrogen for the crop. The clovers survive the winter, and in the spring, we mow off the dead broccoli stems and let the clover grow. If all goes well, we keep the clover mix for a whole year (our Green Fallow Year), feeding the soil and eliminating weed seeds. We mow it to prevent the crimson clover seeding (which could be a nuisance) and when ever any weeds seem to be gaining. Here’s a couple of pictures from a previous year. (That’s our Dairy Barn by the side of the driveway, and our Hay Barn in the distance.)

Broccoli in fall after the clovers grow. Twin Oaks Community
Broccoli in the late fall after the clovers grow.
Twin Oaks Community
In March, the old broccoli trunks are surrounded by a sea of green clover. Photo by Kathryn Simmons
In March, the old broccoli trunks are surrounded by a sea of green clover.
Photo by Kathryn Simmons

I’ve written up this method as part of an article for Growing for Market magazine, for the September issue.

And now our bad news – more nematodes in the hoophouse. When we pulled up our early tomatoes, the roots of four of them in one bed were gnarly with lumps. It’s the return of the Root Knot Nematodes.

Credit University of Maryland
Credit University of Maryland

In the early spring of 2011 we found spinach with lumpy roots. We sent some plants with  soil attached, to the Plant Diseases Clinic and got the diagnosis of Peanut Root-Knot Nematodes. We put that half a bed into a series of cover crops, (wheat and white lupins in the winter, French marigolds and sesame in the spring) and solarized it each summer, for two years. In the summer of 2013, we grew Mississippi Silver cowpeas there (resistant to RKN). This past winter we grew lettuce in the that affected half-bed. We benefited – no sclerotinia drop in that lettuce crop, thanks to the summer solarization!

Meanwhile in the early summer of 2013, we found some beans with lumpy roots in the other half of the bed, so we started the same treatment there. Next summer (2015) we could grow the cowpeas there.

Our first (baggy) attempt at solarization in the hoophouse. Credit Kathryn Simmons
Our first (baggy) attempt at solarization in the hoophouse.
Credit Kathryn Simmons

But now the next bed over has nematodes. Having a half-bed out of production is manageable, but one and a half is more of a blow. We are considering whether we need to be as cautious, or whether we should accept that some level of nematode infestation is likely in hoophouses in the south. We are looking at various scenarios. This research has consumed all my available time this week. Information about nematodes is sometimes too general to be useful, as there are many kinds other than root-knot ones. Plus, what’s true for Peanut RKN is not necessarily true for Southern RKN or Northern RKN. Grr!

I’ve assembled a long list of tomato varieties resistant to some kind of RKN, although I don’t yet know which of them are resistant to Peanut Root-Knot Nematode. Many, many food crops are susceptible. Most of the resistant crops are ones we don’t want to grow in the hoophouse: Jerusalem artichokes, globe artichokes, asparagus, horseradish, rhubarb, maybe sweet corn (opinions vary on its resistance/susceptibility).

Maybe we could grow West Indian gherkins one summer. We’d get soooo many pickles! It’s a very productive crop for us. One idea was to build a second hoophouse and use the old one for (resistant) strawberries for two years! We’re not really at the place to do that, though, financially or time-wise.

Currently I’m studying a list of biocontrols to see what’s available and affordable. Life goes on. Hopefully we can decide at our crew meeting on Thursday, because we can’t start to implement our fall planting schedule in the hoophouse until we decide about the nematodes.