worm castings and seed starting

dice · January 3, 2013

I have started seeds for the last few years in a base
of coir and perlite, around 6 parts coir to 1 part
perlite, with some kind of fertilizer. Last year I mixed
in 1/2 earthworm castings into most of them, and
I used a pinch of Tomato-tone in a 4" pot instead
for a few of them, maybe 10%. I also bottom watered
at transplant (from a seed-starting tray into the 4" pots)
with a mild solution of fish emulsion, liquid kelp, and
humic acid.

The plants with the pinch of fertilizer grew faster
before transplant into the garden than the ones
with the earthworm castings.

1/2 earthworm castings in a 3-4" pot should be plenty
of fertilizer for seedlings, so I wondered what the
difference was. I finally concluded (ok, guessed) that
the earthworm casting amended seed-starting mix
had lost too much of its air space relative to the pinch
of fertilizer amended seed-starting mix. Worm castings
have approximately the texture of mud, with nothing
in them to provide air space, once the worms are
removed, and they easily flow when saturated, filling
air space in the mix provided by more coarse materials.

So in future, I am either going to mix a seed-starting
fertilizer like Bio-tone into the seed-starting mix
(following directions on the bag for proportions),
mix a pint or so of worm castings into a gallon bucket
of water and then water with it if I am using worm
castings for seed-starting fertilizer, or use something
entirely liquid like SeaCom PGR.

ArcherB · January 3, 2013

Last year, I had the best results with Miracle Grow Potting Mix with Moisture Control. The seeds started in seed starting mix were weak or dead after about a month. Costco should have 3 cu ft bags for about $10-13. Walmart has smaller bags for about $6.50 right now. The bags are smaller, but should be enough for starting my 35 or so plants.

This year, I'm going to stick with the MG and compare that with a bunny manure compost that has been picked over by worms for the past year mixed with the MG and straight compost.

checkerkitty · January 4, 2013

Quote:

Originally Posted by ArcherB

Last year, I had the best results with Miracle Grow Potting Mix with Moisture Control. The seeds started in seed starting mix were weak or dead after about a month. Costco should have 3 cu ft bags for about $10-13. Walmart has smaller bags for about $6.50 right now. The bags are smaller, but should be enough for starting my 35 or so plants.

This year, I'm going to stick with the MG and compare that with a bunny manure compost that has been picked over by worms for the past year mixed with the MG and straight compost.

Did you sterilize your MG before planting your seeds? I'm having a hard time finding a soi I less mix in quantity for a reasonable price. This sounds like a reasonable option.

ArcherB · January 4, 2013

Quote:

Originally Posted by checkerkitty

Did you sterilize your MG before planting your seeds? I'm having a hard time finding a soi I less mix in quantity for a reasonable price. This sounds like a reasonable option.

Nope. I put the mix in the cup, wet it, made a hole with my trusty chopstick and dropped two or three seeds in.

I don't know if it matters, but I use disposable plastic cups, one with holes drilled in the bottom sitting inside another with no holes. It makes a little self watering container. Probably not the best way to do it as it stays wetter than it needs to be, but I have never had a damp-off problem. YMMV, of course. The point is that even if I were to sterilize it, it wouldn't take long to contaminate itself with whatever I was hoping to avoid by sterilizing it in the first place.

checkerkitty · January 4, 2013

I used disposable plastic cups, also. HEB had some tiny white solo cups. I drilled holes in the bottom and put them in plastic shoe boxes. I used MG seed starting mix. I had a little problem with a filamentous mold/fungus that didn't kill any of the seedlings. I resterilized in the oven prior to using the remainder and I still have the same problem in my second set of cups. I know microbes are ubiquitous but I wanted to follow best practices and still had an innoculation. Oh well. I've seen that bag of MG mix at Costco. I'm sure they'll have it again this year. I may just do a trial run with that. I think I may also check into that Bio-tone fertilizer for seeds that dice mentioned above. Thanks everyone!

January 3, 2013	#1
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	worm castings and seed starting I have started seeds for the last few years in a base of coir and perlite, around 6 parts coir to 1 part perlite, with some kind of fertilizer. Last year I mixed in 1/2 earthworm castings into most of them, and I used a pinch of Tomato-tone in a 4" pot instead for a few of them, maybe 10%. I also bottom watered at transplant (from a seed-starting tray into the 4" pots) with a mild solution of fish emulsion, liquid kelp, and humic acid. The plants with the pinch of fertilizer grew faster before transplant into the garden than the ones with the earthworm castings. 1/2 earthworm castings in a 3-4" pot should be plenty of fertilizer for seedlings, so I wondered what the difference was. I finally concluded (ok, guessed) that the earthworm casting amended seed-starting mix had lost too much of its air space relative to the pinch of fertilizer amended seed-starting mix. Worm castings have approximately the texture of mud, with nothing in them to provide air space, once the worms are removed, and they easily flow when saturated, filling air space in the mix provided by more coarse materials. So in future, I am either going to mix a seed-starting fertilizer like Bio-tone into the seed-starting mix (following directions on the bag for proportions), mix a pint or so of worm castings into a gallon bucket of water and then water with it if I am using worm castings for seed-starting fertilizer, or use something entirely liquid like SeaCom PGR. __________________ -- alias

January 3, 2013	#2
ArcherB Tomatovillian™ Join Date: Feb 2009 Location: Austin TX Posts: 200	Last year, I had the best results with Miracle Grow Potting Mix with Moisture Control. The seeds started in seed starting mix were weak or dead after about a month. Costco should have 3 cu ft bags for about $10-13. Walmart has smaller bags for about $6.50 right now. The bags are smaller, but should be enough for starting my 35 or so plants. This year, I'm going to stick with the MG and compare that with a bunny manure compost that has been picked over by worms for the past year mixed with the MG and straight compost.

January 4, 2013	#5
checkerkitty Tomatovillian™ Join Date: Feb 2011 Location: San Antonio, TX Posts: 239	I used disposable plastic cups, also. HEB had some tiny white solo cups. I drilled holes in the bottom and put them in plastic shoe boxes. I used MG seed starting mix. I had a little problem with a filamentous mold/fungus that didn't kill any of the seedlings. I resterilized in the oven prior to using the remainder and I still have the same problem in my second set of cups. I know microbes are ubiquitous but I wanted to follow best practices and still had an innoculation. Oh well. I've seen that bag of MG mix at Costco. I'm sure they'll have it again this year. I may just do a trial run with that. I think I may also check into that Bio-tone fertilizer for seeds that dice mentioned above. Thanks everyone!