December 18, 2012

Peronospora farinosa - downy mildew

 I left the spinach in the greenhouse for a few weeks after discovering downy mildew to watch what would happen.  I was not disappointed.  Besides turning fuzzy, the spinach leaves turned yellow and eventually shriveled up and died.
The above picture shows downy mildew sporangia, which I think must be what I called the 'fuzzy' grey stuff on the spinach leaves.  The sporangia is where the spores are formed.

The fungus 'ate' through these leaves! Gross!
What is the plan of attack for next semester?  Not growing spinach is not an option.

  1. Leave the greenhouses spinach free for at least two weeks.  Downy mildew is specific to spinach.  Without a host it should die.
  2. Sanitize the flats I use to grow greens in.  At the end of the season they are pretty dirty and the plant residues on them could harbor spores.
  3. Use a spinach variety that is resistant to more strains of downy mildew.  Since it is such a widespread problem, new varieties of spinach are bred to be more resistant.  Space, the variety I have been using, is resistant to strains 1-3.  In the spring I'll use a variety that is resistant to at least strains 1-7.

December 15, 2012

Salad mix for the end of the semester

I know salad and the end of the semester don't really have anything to do with each other.  It's not as though not having to go to class makes me really, really want kale or something.  The end of this semester is worth celebrating because I am done taking classes - forever!  (Unless I decided to get another degree sometime.)  Of course, the class part is fun, it's the exam part that isn't.
Most of my salads contain something red because it is just so pretty.  Cucumbers, tomatoes, peppers and all other summer time vegetables seem a memory in the distant past.  Right now red greens (ha!) are what make salad more interesting.  And feta cheese, which has renewed my salad consuming capabilities to an all time high.  

December 13, 2012

Baby pak choi, a semi-failure

I have been putting off writing about baby pak choi for a week.  Maybe because they fall in my semi-failure category of greens.  The variety is Shanghai, a green stemmed variety from Kitazawa (High Mowing also supplies it).  I don't totally remember why I picked it except that it is a 'high yielding, cool season annual.'  It forms an hourglass shape and is pretty much grown for its flesh petioles (the bit that connects the leaf to the stem). 

 Growing a sexy, hourglass figure when you're crammed into a tray is kind of hard.  This is why I called it a semi-failure.  I got to eat some hand selected, delicious baby pak choi, but no one else did.  They variety just did not work as a baby green for the growing system we use.  I bet if they were grown in-ground with a bit more space instead of in trays they would be a brilliant (and high grossing?) crop.

*What is the proper way to spell pak choi?  Recently, I've been using a 'K' as Kitazawa does, but High Mowing using a 'C'.

December 11, 2012

The greenhouses

All the greens I grow are in these two identical greenhouses.  I think they were built before I was born.  This summer their plastic coverings were replaced.  Proper greenhouses have two layers of plastic covering them.  On these two the top layer is regular greenhouse plastic and the  bottom layer is fancy IR plastic with an anti-condensation coating. Air is blown through the two layers to help insulate the greenhouse from the outside.  It's like a big, clear, puffy coat for the greenhouse instead of just a raincoat.

                                           Which would you rather wear in the winter?

The heater and fans are controlled by a complicated control board (above right) which I only have to set once and then it does all the work.

At either end of the greenhouses are great big fans which turn on in a three step process if the temperature gets above 75 degrees.  (I also measure the light with the little box on a stick on the left and hourly temperature with the white boxes four benches down on the right.)

If the temperature is lower than 75 degrees two little fans (in the upper right hand corner above) are always on to circulate the air.  This is one way the powdery mildew spores got spread around.  Since one set of fans is always on, it is always noisy.  

Circulating the air is super important on hot and cool days.  Right now air circulation is very important for spreading hot air from the heater around.  Each greenhouse has one of these propane heaters.  Hot air blows out the round part on the right.  On cold days I stand right in front of it to warm up. 

December 7, 2012

Salad mix of the week

This week has got me a bit blue.  Maybe because it's cold and grey outside.  Maybe because all the spinach is dying.  Or maybe because all the tat soi is gone.  Tat soi has such lovely small round leaves.  When paired with frilly fun jen and bright red beets I am cheered right up!
In this mix tokyo bekana could easily be exchanged for fun jen.  With age beet greens get even redder, and taste more beet-y.  If you took out the lettuce, all of these could be quickly wilted in a hot pan.  I'm starting to get hungry.

December 4, 2012

Early morning at the greenhouse

Sometimes it still feels dark when I get to the greenhouse early in the morning.  The past few warm days have caused lovely fog over the fields, and wetlands.