April 26, 2013

More on Vates kale

I wrote about vates kale about a month ago.  Two harvests later it's still going strong.  Whether or not a variety is a good cut-and-come-again green when grown on benches is something I started to assessed this week.  Kale seems to be a good contender.

April 23, 2013

Where have I been?

It has been awfully quiet in the wintergreens blog world recently.  First, because I was sick and then because I was busy catching up on everything I put off while being sick.  
Last week I helped with the planting of a school garden.  Over the course of a day a few hundred kids trooping in and out of the garden to plant lettuce, spinach and tatsoi.    In the picture rows or greens are marked with string and the tatsoi beds are hidden under row cover.  I was chuffed that the greens planted followed the same pattern as the greens I primarily study: a lettuce, a spinach and a brassica.  The kids remembered eating lettuce and spinach in previous years, but not tatsoi.  The day was fun, but rather exhausting.  I forgot what it was like to work with kids.  I also forgot to put on sunscreen.
The daffodils are finally blooming in New Hampshire, and the growing season is about to being for most gardeners.  The beginning of the outdoor growing season means the end of the indoor wintergreens season is quickly approaching.  Last week was the last big harvest of greens.  Yesterday I took my last leaf length and harvest weight measurements.  The greenhouses are emptying rapidly.  Soon I will be spending most of my time on the computer crunching numbers.

April 16, 2013

Canton noodles with greens and cusk

There comes a time in every gardener/salad growers life when they get tired of eating salad.  Diversity is decidedly necessary in the diet.  Once we feel as though we can't shovel in another mouth full of salad (even if tangy cheeses or dried cranberries are involved) we start cooking the greens.  

This was dinner a few nights ago: stir fried noodles topped with sautéed brassicas, ginger, onions and cusk.  Cusk is a native white fish.  Supposedly it's related to cod, but the texture is quite different and it seems to work best in dishes that require broken up pieces of fish (like chowder or fish tacos).

April 10, 2013

Colletotrichum: another spinach disease

I've been sick this week, and so is the spinach.   This new spinach disease is Colletotrichum (aka anthracnose).

Symptoms include: tan-brown circular lesions that coalesce  resulting in severe blighting of foliage.  Lesions can also be water-soaked, as in the below, righthand picture. Eventually diseased tissues are covered in small black fruiting bodies (the 'mushroom' part of the fungus).

Colletotrichum is seed borne, so using disease-free seeds is the best way to avoid it. I've heard washing seeds in hot water will kill this kind of disease, but I think you need a special seed-dishwasher.  (Does anyone know about seed washing?)

This is the second really gross disease spinach has had.  (Remember the downy mildew problem last fall?)  This leads me to a very bold idea:

Maybe spinach is not a good crop for bench-top winter growing.

Here's why:
  • Spinach is susceptible to many diseases when grown in greenhouses.  
  • Spinach is slow growing.  It has a slow turnover time.
  • Spinach takes a long time to harvest.
  • Spinach can have low yields per square meter. 

Note that I'm being specific to bench-top growing, and also that I said maybe.  There are big differences between bench-top growing in trays (what I'm doing) and in-ground growing (what farmers/gardeners do).

April 4, 2013

Releasing parasitic wasps!

The second biological control I released in my attack on the aphids  were Aphidius ervi wasps.  There were ordered from Biobest.  Parasitic wasps are SO COOL (this is coming from a girl who is terrified of yellow jackets and hornets).  
As their name implies these wasps lay their eggs in aphids.  When the eggs hatch the new wasp goes through all it's juvenile life stages inside the aphid and eventually emerges as an adult, thus killing the aphid.  The dead aphid is called an aphid mummy.  You can see A. ervi in action below.  The aphids don't even seem scared.  Why aren't they running away?

The wasps come as eggs in aphids and are packed in buckwheat hulls (that's what you see in the photo below on the left).  I placed saucers of buckwheat and aphid eggs around the greenhouse and left them there for a week.  I had high hopes of seeing something exciting.

Alas, I have yet to see a wasp.  They are really small and they don't sting.  Other greenhouses on campus use these wasps to control aphids, which is how I took the picture on the right.  See how small they are?  If you're eating you might want to swallow your bite before watching the video below.  Pretty cool huh?

April 1, 2013

Releasing ladybugs!

In the past few weeks I've been working on part three of my attack on the aphids byt releasing ladybugs and parasitic wasps in the greenhouses.  It has been fun!

The ladybugs come from A-1 Unique Insect Control.  They came in a loosely woven cotton bag and were kept in a fridge prior to release.  I sprinkled them over the greens concentrating on areas that I knew had lots of aphids.  Once they warmed up the ladybugs became very active and few all over the place (even up my pants!).

Ladybugs are aphid eating machines, supposedly. I've tried really hard, but have yet to see any I've released actually eating an aphid.  The aphid population has decreased, so they must be doing something.  Eventually they settled down and then seem to spend all their time in warm spots.  Like the edges of trays or the sunny side of the greenhouse.