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#119 - Step-By-Step Active Composting - Day 9

Welcome to Day 9 of Pile #1, and Day 7 of Pile #2. We had a very warm day yesterday at 95 degrees which is hot for Hawaii. It has been in the mid 90s for the past couple weeks now.

I know everyone thinks Hawaii is so much hotter than the mainland US because we are so much closer to the equator, but it doesn't quite work that way. This is the hottest it ever gets here. Unlike the mainland, here in Hawaii we do not get up to triple-digit temperatures, other than in my compost piles.

Luckily the Trade Winds act as a natural air-conditioning to keep the islands cool. Unfortunately, we will loose them in August or September for a few weeks and it will feel unbearably hot until they come back.

Ok, so this morning when I checked the temperatures of the piles I noticed that Pile #1 is running at 130 degrees which is a tad lower than I would like to have it. It is still within the "Active Hot Compost" range but it isn't composting as efficiently as it could be, so I need to heat that one back up just a little bit. I like to keep my piles between 140 and 160 so they are working most efficiently.

By the way, I forgot to mention this before, ignore the green markings on the thermometer. Those ranges are not for the type of "hot" composting that we are doing. According to that thermometer you would want to keep the temperature below 130 degrees which at that temperature does not kill off weed seeds and harmful bacteria and plant diseases that may be in the pile.

Even the FDA says that the pile must reach at least 135 degrees for several hours to kill those things off to create safe compost. Which is why I do not do the slow cold composting method where the temperatures never get over about 110 to 120 degrees.

To increase the temperature of this pile I will be turning it over to introduce oxygen, adding some nitrogen in the form of food scraps that I have run through a blender to break down into as small of pieces as I can, and wetting the pile down again. A bunch of McDonalds cheeseburgers, some rice, and some left over chili should do the trick nicely.

As I stack the pile back up I am trying to get the pile as tall as I can which also helps to generate more heat inside it. One of the things that you will notice with composting is that the temperature of the pile declines over time as the size of the pile gets smaller. By piling it back up as tall as you can you can temporarily overcome some of this volumetric heat loss.

I am seeing a lot of fungus activity inside this pile which does not surprise me because I did not turn it yesterday when I turned the other pile so it started getting a little bit anaerobic but not enough to start creating any unpleasant odors yet. Getting it turned over and getting the temperature back up on it will help with that.

Pile #2 on the other hand is my "problem child" pile. I have had temperature control issues with this pile since I started it a week ago.

As you can see we are still staying just above 160 degrees. It is almost like the pile is taunting me. No matter what I do, I just cant get it below the 160 degree mark. The pile is mocking me, but it does not know me very well. I do not give up. I have more tricks up my sleeve to control temperature that I haven't used yet.

Let's go ahead and turn this pile again to get some more oxygen inside there. As I am turning it I notice that it is getting a little on the dryer end of the moisture scale than I would like, so we will take care of that by wetting it all back down again.

This time though, instead of just turning the pile as I normally would by moving it from bin 3 over to bin 2 in the middle, I break it down into two separate piles. By reducing the amount of composting material it does not have the biomass necessary to generate as much heat as it did before. This is basically like if in the winter time you were to be standing outside in the cold and someone were to take your nice thick warm coat off of you. It would cool you down quickly. Reducing the size of the pile has the same effect.

Both piles should still have enough biomass to maintain the 130-140 degree range when they heat back up later today. They both temporarily dropped to 125 degrees but once they are watered back down the temperatures will climb back up again, but they should not be able to get over 160 now. I will teach this pile who is boss, one way or another.

Pile #1 dropped down to 115 degrees, but after giving it the table scraps earlier and wetting it back down it will be warming back up in the next few hours. Hopefully I can get it back to the 140 or 150 degree range. There is still a lot of plant leaf material in this pile that needs to be broken down so I need to keep this pile as hot as I can to break it all down.

Normally I would have never used plant material this large in a hot compost bin because it takes much longer for it to break down. The larger pieces the material are in, the longer they will take to decompose. I did not have an easy way of breaking this material down though, so I had to just go with it.

I have ordered a new wood chipper/mulcher that is on its way here. It was delivered to Home Depot over in California today, so they will be shipping it over to Hawaii in the next couple weeks so that I can ick it up at the local Home Depot store here. Once that gets here, one of the first things I am going to do with it is run pile #1 through it to break down this large leaf material some more so that it can compost easier.

I would normally never run an active pile through a machine like this, but I don't have much of a choice at this point. I need to get this material broken down finer and if that means sacrificing some of the microbes that are decomposing the pile I will just have to live with that. I will be sifting out only the larger material to run through the machine so the rest of the pile will still have the beneficial microbes in it to reproduce once again. It may set me back a few days in the process, but it will save me months of time overall.

We are getting a nice dark color to pile #1 which is a good sign that everything is working correctly. Pile #2 should be darkening up in a few days as well, it is showing more tan and grey colors in it already. There are still a few blades of grass in it that are bright green, but each day I am seeing less of that.

We are basically at about the half-way point for Pile #1, and with the way it is looking it will be ready to use very soon. I just have to get that large leafy material to break down now, the rest of it is almost ready to go.

Ok, all three piles have been turned and soaked back down. I will come back this afternoon and check their temperatures again, but that should be about it for today.

With about 20-30 Manilla Palm Trees in my yard, I wish I could figure out a way to compost the palm fronds that keep dropping in my yard every day. Unfortunately, every time I have tried to compost them it ends in failure. They just take way too long to compost and I do not have the room to have a cold compost pile running for years at a time just for palm fronds.

Palm fronds are one of the few things in nature that will also destroy a wood chipper, so I will not be trying that again. I have ruined 3 wood chippers over the years trying to compost palm fronds, now I just load them into the "green waste" bin and let the city deal with them. They have more resources available to them than I do.

Until Next Time,

Aloha & 73


Ok, I rechecked the pile temperatures this afternoon and Pile #1 is back up to 135 degrees, so hopefully it will continue to climb just a little higher. Pile #2 which I broke apart into two smaller piles this morning to cool them down have cooled down, but only slightly. Even though both piles are only about 2 feet tall now, they are both running at 160 degrees. I will keep an eye on them over the next couple days.


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