Compost Tea

During one of my Brooklyn Botanic Garden classes I learned how to brew compost tea. My teacher, Jenny Blackwell, is the project manager for the NYC Compost Project in Brooklyn and is obsessed with composting. She was raving about how much better it is to brew compost tea for your plants then to just topdress them with compost. It is great for container gardening because it adds biology to your containers without adding extra weight and makes a small amount of compost go farther by diluting it.

Also, I can't believe I haven't mentioned my vermicompost on this blog before! My friend Crystal is mortified that I have a small composting bin in my closet ("But what about your clothes!?!"). It doesn't smell and it's not that gross. I swear. I built it myself in a class at 3rd Ward and started it about a year and a half ago. I throw any left over food scraps into my bin (egg shells, left over veggie scraps, old flowers, coffee/tea grounds, etc.), add some torn up The New York Times, and tons of red wiggler worms eat it, digest it, and poop it out. It's the worm's poop that your plants want. Especially tomato plants because they love Nitrogen. Hope you aren't eating lunch while reading this post. :)

So, the materials you will need are: a 5-gallon bucket, 1-1/2 to 1-3/4 cup of fresh vermicompost or worm castings, a fine mesh cloth (I used cheese cloth), 1 tablespoon of unsulphured molasses (you can get this at the grocery store near the maple syrup), an aquarium pump with at least 40 gallon capacity (pet stores have them), tubing to attach to the aquarium pump (also at the pet store), and something heavy to keep your mesh bag of compost submerged in the water (I used a mug).

First, I made a little mesh pouch for my compost by spreading out the cheese cloth and securing it with some string.

Then I set up the air pump and tubing, while also filling the 5-gallon bucket with warm water, 60-85 degrees. Rain water is best, but New York City tap water will do.

 

Plug the aquarium pump in and start to aerate the water before your put the compost in. It is VERY important to keep the water aerated. As soon as the aeration stops you run the risk of having your compost tea turn from aerobic to anaerobic and you may be adding bad bacteria to your plants instead.

Hang the bag of compost on the side of the bucket and begin to steep it as you would with a normal tea bag. Next, add 1 tablespoon of unsulphured molasses. The aeration is keeping the beneficial bacteria alive and the molasses is feeding them.

Secure the lid on your bucket and leave it for 24 to 36 hours. If it starts to smell, add more molasses. After a day and a half mine looked like this:

I think that it could have been a tad bit darker, maybe if I left it for another 12 hours it would have been, but I was anxious to get it on my plants. The past few days have been scorching hot and they are really starting to look sad despite my best efforts to water them constantly. So, taking the brewed compost tea, I dumped it into a watering can and then proceeded to water the whole plant: the leaves, stems, soil, flowers, the whole thing. Another benefit of compost tea is that the good bacteria will stick to the plant's leaf surface and keep any menacing bugs and bacteria away. I ended up using all 5 gallons just dousing the plants with the murky brown water.

Hopefully the compost tea shower will make this 100-plus degree day a little bit more enjoyable for my emerging tomatoes. If you try this at home make sure that you use your freshly brewed tea within the first 5 hours to make sure that all of your beneficial bacteria and nutrients are still alive. I will definitely be trying this again next month. Happy composting!