Ants on Radishes

I planned to make a spring salad tonight, and what could be better than adding a few crunchy, spicy radishes to top off some micro greens? Radishes, like many vegetables, are so much better fresh from the garden that they almost seem like a different vegetable from what you get in the grocery store. Plus, they grow from seed very fast and easy in early spring.. This year, I am growing Cherry Belles from Territorial Seed. 

Anyway, I've been checking on the radishes fairly frequently lately, since they grow so fast.  About a week ago, I didn't see any ants.  Today - a lot of ants.  They are small and black.  They seem to be tunneling, as well as crawling on top of the soil quite a bit.

The radishes actually seem fine so far.  I didn't see any damage on the leaves, and most of the mature radishes' red shoulders look unharmed.  But perhaps the ants only just arrived and their damage isn't yet apparent to me.

I will try to post some pictures of them later today.

***UPDATE***

Oh, how wrong I was.  This evening when I pulled some radishes, I discovered some serious ant damage.  They appear to have shaved chunks off of the radishes.

First, here is a "before" picture of radishes I picked a week ago, with no damage:

Now here are the "after" pictures of the radishes I picked today:

    

One of the radishes was even worse - a mere splinter of a radish.  When I pulled the radishes, there were so many ants, it looked like the soil was moving.  Ugh.  Here's a close-up of the ants on a rock, where you could see them:

What do I do?  Most of my radishes remain in the ground, and I don't want to lose them all. 

***UPDATE***

Tonight I found the same bug on two of my radish plants.  The ants are still all there.  This second bug was nestled in the very lowest part of the radish greens, just kind of hanging out, not moving or anything.  The ants were moving all around them.

I picked the bug off the radish and held it in my palm to take a picture.  At first I thought the bug was dead, because it didn't appear to have any legs, and it rolled around in my hand like a dead thing.  Then the weirdest thing happened.  All I had was my phone to take a picture, so I fumbled around a bit.  While I was fumbling with the camera, all of the sudden the bug came to live and started wriggling.  It was like the thing was asleep, and then it woke up. 

I took a couple of pictures as best I could and then snapped its head off.

Like I said, I found these suckers on two different radish plants.  Perhaps they are the real culprits.  Thoughts?

***UPDATE***

I talked to Amy on the phone about the problem, and she said that the ants probably aren't the ones doing the actual damage. But ants are often a sign that there's some other pests at work you just can't see. For example, ants like to "farm" aphids - but I know what aphids look like, and there are no aphids on my radishes.

Amy suggested I try diatomaceous earth as well as Bt, both natural pest deterrents. these would take care of a variety of potential pests.

I had some Bt on hand, so I sprayed that on the radishes about 3 days ago. I don't have any diatomaceous earth but plan to go pick some up soon.

Results so far: the Bt seems to have worked!! It took a few days to see a noticeable difference, but this morning when I checked the radishes, I saw that the ants are almost all gone and the damage to the radishes seems to have slowed and/or stopped.

My Big Fat Earthworm

I was in the garden this weekend fluffing up the soil and adding compost when I unearthed this bad boy. Maybe it doesn't seem huge in the photo, but let me tell you this worm was the biggest, thickest one I've ever seen in the garden.  When I first spotted it, one segment of the body emerged from the dirt, and I thought it was a massive grub.

Is this just an overweight earthworm?  Are there any types of earthworms that are bad for the garden?

Using a Soil Testing Kit

In 2006, I built raised garden beds and filled them with a truckload of fresh soil from an organic supplier in Seattle.  Each year since then, I've added generous helpings of compost from my own compost bins.  In other words, I knew my soil was good from the start, so I never saw the need to test my soil for pH, nitrogen, and the like. 

However, last summer I noticed a real slow down in my garden's productivity.  All my vegetables struggled, especially tomatoes and beans.  At the time, I chalked it up to the fact that (a) we experienced one of the coldest Junes on record, and (b) I discovered symphylans, aka evil lifeform nodes, festering in the soil.  (More later on the symphylans.)

While the cold temps and evil lifeform nodes contributed to last years' disappointing crop,  now I'm thinking that declining soil fertility might be an accomplice.  I recently came across this article that says compost does not contribute the necessary N, P and K to maintain proper soil fertility to grow vegetables.

My compost bin system digests primarily yard waste - grass and leaves and clippings - with some food scraps mixed in.  I don't add anything else to the compost, like bone or blood meal, kelp, etc.  Which means that if my grass and yard clippings are all lacking in certain nutrients, the compost will be deficient too.  The fact is, I have no clue whether my soil has sufficient fertility or not.  Why not find out? 

I bought this $7 kit from the garden nursery with little test tubes and colored pills.

 

Green = pH

Purple = Nitrogen

Blue = Phosphorus

Red = Potash

Timing - I administered the test on March 9, two weeks after I had applied compost to the raised bed where I tested the soil.  

According to this test, my pH, phosphorus, and potash are fine, but I'm low on nitrogen.  The tube with the purple cap is the nitrogen tester.  How accurate is the test?  There's an interesting discussion of that question here: http://www.waynesthisandthat.com/soiltest.htm

Even if the tests aren't 100% accurate, I'm not all that surprised that my nitrogen is low.  In fact, I'm kind of glad!  Low nitrogen is a much easier problem to fix than climate change (abnormally cold June) or symphylans (evil lifeform nodes that not even Monsanto can figure out how to kill).  

 

Now I need to explore some options for increasing nitrogen that don't involve little blue crystals .  .  .