On the origins of lettuce

Did you know there are six groups of cultivated lettuce?  I only grew lettuce from one of these groups - romaine - during the past two years.  

To read the rest of my post on the origins and cultivar groups of lettuce visit feedthedatamonster.com.

"Basics for winter, bench-top salad green production" part two on Floricast

Part two of Basics for winter, bench-top salad green production is now up on Greenhouse Grower as an episode of FloriCAST.  You can see it here!

The brassica family (again)

Exploring the Brassica family and how many of the plants I grow is a topic I have written about here and here.  Last week I wrote a third piece on this group of crops, which can be seen in its entirety at feedthedatamonster.com.

(What is feedthedatamonster.com? A collection of researchers who write about interesting science-y stuff.  Go take a look!)

"Basics for winter, bench-top salad green production" on Floricast

In late July I put together a slideshow on basics of winter salad green production on bench-tops for the video podcast Floricast. Last week it came out and you can see it here! If you've been following along this blog you may recognize some of the information and pictures. I believe it's the first time we've started to take all the experience and data from the past year and begin making it into more public-ready formats.

Where have I been?

I haven't written anything in . . . over a month!  In part because this is a blog about winter salad greens (it may be pretty cool outside for August, but it's definitely not wintery), but mostly because I've been working on finishing my thesis, and working on extension reports.  The end is in sight!

What information would you like to see?

Graphs? Tables? Information on seeds? varieties? media? profitability? planting dates?  Let me know, and I'll write about it!

I'll post, or link, extension publications in the new 'research reports' tab once they come out.

We feed old greens to nearby goats.  Right now too much kale is definitely a problem.

Thesis defense postponed

I've postponed my thesis defense to sometime in September.  I was given the option to take a bit more time and jumped on it.

Biological control graphic

I found this unused graphic while cleaning out a 'pictures' folder on my computer. 

Thesis defense date set (the end is in sight)

It has been quite around here recently hasn't it?  With my thesis defense just one month away I've been working on the not-so-fun parts to research - writing.  The goal is to have useful growing information ready for use ready about the same time since most of it will be part of the thesis anyways.  So, the end is in sight and quickly approaching!  

Greens in the garden

We went away for a long weekend and came back to a garden bursting with greens.  The swiss chard above is interplanted with leeks.  I chopped it down, and pulled some plants out to give the leeks more room to grow.

The other green I pulled out was the vitamin green.  I had such high hopes that it would push through the bug problems but I was wrong.  Or maybe I'm just too lazy to deal with all the bugs.  Hole-y leaves aren't that appetizing anyways.  So I pulled it all out and planted basil in it's place.  I'll try planting it again later this year and keep row covers on to keep the bugs out!

We have a lot of other vegetables growing in our garden, like the scallions above.  Aren't they cool looking when they emerge?  Our garden neighbor is growing a lot of mesculn mix (above right).  I counted at least five varieties of greens.  Can you name any of them?

Salad greens in the garden

About a month ago, when salad green production in the greenhouses was starting to slow down I had a bad thought:

"What I am going to eat when the salad runs out?"

I  took some of the flats of greenhouse greens that had been harvested, divided them up and stuck them in our outside garden.  You can see the swiss chard above is still planted very close together - not at all the recommended 4-6 inch spacing between plants.  I wasn't about to untangle all 150+ plants that were in the flat.  Since the plants are so densely packed we harvest leaves are still pretty small - about the size of my hand.     

I also squashed in a flat of red russian kale.  Given more space to grow its leaves are much broader than when grown in the greenhouse.  Hand-sized leaves mean it's still tender enough to eat in salads or on sandwiches.

Lastly, vitmin green.  Like red russian kale, vitamin green really spreads itself out when given more space.  The broad leaves are mild and tender.  Beetles seem to like eating them just as much as we do.  If I had been smart I would have covered the plants right away with some lightweight row cover.  Now it's too late.  Covering the plants would probably trap pests in.  I don't mind the holes since I'm not trying to sell these greens.  Other brassicas that beetles like include arugula, mustards and napa cabbage.  See here for more information on managing flea beetles in brassicas.

UNH Today! Wintergreens is in the news!

Since I have finished growing and measuring salad greens I've spent most of my time inside, on the computer, wading through all the data.  This is the not-so-pretty part of research.  The plants are long gone to the compost pile, and I have yet to figure out any super exciting results.

In the meantime, take a look at this article in UNH today which features the wintergreens field day back in March.  Pretty cool!

* An update a few hours later - the UNH Cooperative Extension website has the same story - with a bigger picture!

Organizing salad greens by yield

When looking at yield data collected this past spring, I found the salad greens I've grown could be roughly categorized into three groups: heavy, mid and light weight.  These distinctions could be useful when building a unique salad mix with some lessor known salad green varieties.

The highest yielding greens were the lettuces and loose headed cabbages.  These make a good basis for a salad mix because they are a) heavy and b) mild tasting.

Medium yield greens contain some of my favorite greens.  Ok, they are all my favorites and when mixed together they make a nice salad.  None of these have any spicy-ness, but they do offer good tastes and nice curvy leaves.  And beets and chard just so pretty.

Spicy mustards, arugula and kale make up the light weight category.  They are 'lofty' and add texture, color and interest to salad mixes.  Often, these are the greens that you don't want too much of in a salad anyway.  I've tried the mainly-mustard-greens salad and it was too much. The keyword there was 'tried.'  Other varieties of kale may produce a heavier yield, but the russian kales have rather spindly leaves when they are young.

What would you choose to put in your salad mix?

Bolted brassicas

Right now the greenhouse is filled with bolted, flowering brassicas.  Most brassicas have yellow flowers.  Arugula flowers are totally different in color - they are cream colored with red viens.  They do have the same number of flower petals and stamens.

Brassica florets are tasty when small, but once the stems elongate and the flowers open they are tough.  Last year I have enough tat soi flowers to eat in a stir fry. This year I let everything bolt.    Brassicas tend to bolt quickly in this greenhouse because there are so many plants in such a small area.

Varieties, clockwise from top left: wasabina, arugula, mizuna, tat soi, chinese pac choi, tokyo bekana.

What did I plant? Telling apart sprouted greens

Does this happen to you?  Do you plant things and forget what they are?  I certainly do! (See vates kale.) It's pretty easy to tell what family salad greens are in based on their cotyledons.  You might not be able to tell what variety is growing, but at least you'll be able to tell the lettuce  and spinach apart.

When lettuce sprouts it's small and cute - the bunny of the salad greens.  The cotyledons spread wide open on the soil surface.  Red varieties of lettuce will change color if it's warm and sunny. 

Spinach cotyledons are long and slender, forming a 'V' shape.  

All brassicas have heart shaped cotyledons.  This includes leafy greens and cole crops (cauliflower, cabbage etc).  The picture above shows tokyo bekana, kale and scarlet frills.  Cotyledon size varies between varieties, and so some brassicas make good microgreens.  Broccoli, although not a salad green, is a good example.

Members of the beta family, including swiss chard and beets, are also good microgreens because their stems are often bright colors.  I've taken a lot of photos of them because of this.  Their cotyledons are oblong with a slightly pointy tip.

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.

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.

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).

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).

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).  

Source

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?

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.

Field Day: Media Trial

Field Day: Growth Rate

Field day: Germination

Field day!

Yesterday 92 people crammed into the greenhouses to hear about salad greens.

92!

Over the next few days I'll be posting the material from the field day.  It will all be easily searchable by clicking on the new Field Day icon in the right hand sidebar.

Field Day: Variety Trial

What is a 'baby' sized green?

There is no standard size to define what is considered a 'baby' sized salad green - at least I haven't seen one yet.  So I made up my own set of parameters based on observation, salad eating and a few reliable sources.  Johnny's Select Seeds suggests harvesting salad greens at 4-5 inches tall  which translates to 10.16- 12.7cm.  I feel like Eliot Coleman of Four Season's Farm wrote that he harvests salad greens at 4 inches, but since I can't find that anywhere in my notes I could be wrong.

For harvesting and data analysis I consider lettuce and brassicas in the 8-12cm range a good size for baby greens.

Currently, I consider 6-10cm perfect size for spinach.  Unlike lettuce and brassicas, spinach has an official size: the size of a soup-spoon (again I can't find my notes on this right now).  I don't have real soup spoons, but hopefully a tablespoon is an ok substitute.

Field day preparations

I've spent the last few days preparing for the field day, which is only five days away!  The posters are made, and all that's left is cleaning up the greenhouses.  Happily, they survived the heavy, wet snowstorm on Tuesday.

Now that daylight lasts all the way till 7pm greens are growing quickly.  Sometimes as much as a centimeter a day!

Cut-and-come-again greens

Nearly all the greens I grow are considered cut-and-come-again greens.  But what does that mean? And why haven't I ever mentioned it before?  First think about how salad greens grow: new leaves come from the growing point, which is at the bottom of the plant.  If you don't cut off the growing point when harvesting, new leaves will emerge and you can harvest a second time!

Brassicas, like the kale and mizuna above, make really good cut-and-come-again greens.  They are fast growing and often have jagged leaves that hide any past scissor marks.  Leaf lettuce is not quite as good as a cut and come again green because it is slower growing and because it doesn't hide past harvest cuts well.  In the right hand picture below you can see a very flat-topped lettuce leaf that wouldn't look so nice in a salad.

Spinach is a good cut-and-come-again crop because it's leaves are on longish stems.  Spinach is slow growing, so plants grown on benches, in flats may run out of nutrients before they are big enough to be harvested a second time.  

A second harvest from greens offers the chance to have additional salad greens without much extra labor or materials.  This spring I'm going to asses the regrowth on greens to answer these questions:

• How do regrowth yields compare to first harvest yields?
• Does the quality of the regrown greens change?
• Are some greens better suited than others for regrowth in a bench-top system?