Sometime ago I extolled the benefits of making and using compost in the garden. A short list of benefits associated with compost include: adding important nutrients to the soil as well as increasing water holding capacity, soil temperatures, and nutrient holding capacity (often called cation exchange capacity for you soil geeks out there). In short, it’s pretty awesome stuff. However, there is another way of getting compost to the plants in a speedy and efficient fashion: compost tea.
As the name suggests compost tea is a liquid that is made from an infusion of compost. But, it can be a little more than that. At its most basic form you can add compost to a bucket of water and let it sit for a couple of days. This will get you some of the fertilizing benefits but not the whole shebang. But, why do it in the first place?
For starters, compost tea acts as a liquid fertilizer. Stewing the compost will release most of the nutrients stored in the compost. Since it is in a liquid form the nutrients are more readily available for the plants to be used. Second, by letting them stew, and going a step further than the most basic form, you add and increase beneficial soil bacteria that will help convert the (here’s a short bit of basic biology/chemistry) organic forms of nutrients (not like ‘oh is this soy latte organic?’) to inorganic forms of these nutrients which the plants can uptake. It’s like a quick jolt of java juice for your plants and a method that many organic gardeners swear by. In fact, my brother-in-law, the head groundskeeper at a college, puts it on everything including the turf for the sports fields.
What You’ll Need to Make Compost Tea
- A five gallon bucket
- Cheese cloth or panty hose
- A string to suspend the tea from
- Liquid seaweed fertilizer (optional)
- Blackstrap molasses (optional)
- Fish tank aerator and tubing (optional)
Compost Tea in Five Simple Steps (or Fewer)
- Start by filling the bucket. If you have municipal water, let it stand for a day before you start the brew. This will allow most of the beneficial bacteria-killing chlorine to off gas.
- Next take a scoop of about 2 cups of compost and dump it into the panty hose or cheese cloth. We’re not going to judge you either way. If you do use panty hose, use the real thing and not those fishnet versions you have tucked away in the closet. This acts as your tea bag and allows the nutrients to infuse into the water while the bits stay out. This isn’t loose-leaf tea after all.
- Pour in a couple of tablespoons of both the other feeds. The seaweed fertilizer has a couple of micronutrients that aren’t always found in compost and the molasses adds a sugar base for the bacteria to thrive on.
- Next, plug in the aerator and let the bubbles tool away for about two days. This helps aerobic bacteria grow. You’ll know when the tea is done when a layer of non-fish tank aerator bubbles forms on the top indicating the bacteria are really cranking.
- Finally, pour this on your plants. You can dilute this mixture with water (providing you let that water off gas as well) to get more mileage out of your new batch of liquid gold.
Creating your own compost tea will give you a nearly endless supply of liquid fertilizer for free. It’s also pretty hands-off for a DIY fertilizer. You should start to see benefits nearly overnight (which in gardening terms is in a week or two). You’ll also transform into an organic gardener (as in ‘is this soy latte organic?), if you aren’t one already.
Note: Most seaweed fertilizer will say it’s organic and for vegetables, but will often have a warning that it has trace amounts of this metal and that. The seaweed is harvested from the ocean where it can trap what’s in the water. The metals are presumed to be there just like they would be in tuna or other fish and therefore they label it. If that’s a concern for you, just leave out the seaweed fertilizer ingredient.
For a slightly more involved technique for making compost tea, check out this video from Doug Green: