Soil Blocker......starting seeds without pots

Tronchuda cabbage, newly sprouted

So it's time once again to start brassica crops indoors.  Last year I experimented with making my own "cow pots".  Though initially the cow pots worked out quite well, I eventually found them to be problematic in that they seemed to draw too much moisture from the soil and also constricted root growth too much once the plants were mature.  So, this year I invested in a soil blocker.  It was a little spendy, around $30 from Johnny's Select Seeds.  This was the lowest price I could find.  I didn't manage to find anyone who sold them in Portland.

Below is a photo doc of my first go at making soil blocks.  

My helpers.

First step--mixing the soil.  This involved a trip to Concentrates, in Milwaukie.  Ingredients, from most to least included coco peat fiber, pumice, garden soil, compost, blood meal, dolomite, azomite, greensand and bone meal.  I got the recipe from pottingblocks.com.

After mixing is complete, you make a slurry and then start blocking.

Eqipment:  Bowl of water for rinsing blocker.  Tray for blocks pan of wet soil and an old cloth diaper for cleaning hands before handling the camera!

dip in blocker

Making a what I call a "dirt angel", by twisting blocker back and forth.  

Note that the soil in this pic is not as wet as the first.  This pic was taken on second attempt and drier soil, in my opinion, works better.  You lift and repeat your dirt angel, lifting and pressing in more soil,  about 3-4 times until water starts to ooze from top of blocker.  The trickiest part here is lifting the blocker up without the blocks slipping out.  This is why you don't want the soil too wet, as they won't stay in the molds.  I found that gently tilting the blocker and lifting just enough to "step" onto the next area of soil works best.  Also, patting down a smooth area before each pass is helpful.

 

Positioning.  About 1/8" spacing..... 

ta da !

Finished tray.

So you can see that there are nifty little built in holes for your seeds.  I think some folks just drop in the seed but I covered mine with a bit of fine soil.  Another useful tip is to use a finer grit of pumice or pearlite than is suggested on the website.  I found that for brassica seeds (cabbage, broccoli, kale, etc.), if they have a large pumice piece sitting on top of them then it will be difficult for them to sprout.  Next time I will sieve out the large pieces.

So there it is.  Soil blocks.  So far, so good and it's great to have eliminated yet another plastic (pots) item from my gardening.