Here are the results for a week long incubation test on some char/peat moss mixes.
Char is portioned by volume. The density of the char and the peat moss are very close but I don’t have the #s. I can do so but must oven dry the two and did not take the time yet.
EC units are micro-siemens/cm.
Tests are done using a SME or saturated media extract.
Please note that second table with EC values has been modified due to an error in the setting of the EC meter.
|Peat Moss 5% char||4.4||4.2||4.2||4.3||4.2|
|Peat Moss 10% char||4.5||4.4||4.3||4.5||4.4|
|Peat Moss 25% char||5.3||5.2||5.2||5.3||5.1|
|Peat Moss 5% char||510||450||480||362||400|
|Peat Moss 10% char||540||480||560||480||460|
|Peat Moss 25% char||960||840||1080||760||670|
Petunia Seedlings with Biochar
We did a simple test of mixing 10% biochar with our normal seedling mix and then seeing how Petunias would do.
Here is a picture of the Petunias in our normal seedling mix.;
…and here is a picture of the same variety with the 10% char mix;
It doesn’t come across in the photos as well as it might but you can see some intervienal chlorosis which is likely indicative of iron deficiency.
I tested the EC and it was 1250 for both of the trays. The ph was 6.2 for the normal mix and 7.1 for the char mix. The char has raised the pH enough to cause the iron deficiency. We realy like to grow petunias closer to a pH of 5.5 and should be treating these flats with acid to lower the pH. As it stands both trays have recieved the same treatment.