Store-bought liquid fertilizer can be expensive, especially if you have a lot of plants to feed. Fortunately, there’s a cost-effective, easy alternative you can brew up at home. Read on to learn how to transform simple compost into a nourishing liquid lunch for your plants.
Compost is Perfect Plant Food
In the spring, I turn my winter compost into the pile and scoop up shovelfuls of rich, black, soil from the bottom of the bin. Then, I add the composted soil to my beds, and plant. It’s a great system, and my springtime plants are healthy, happy, and well fed.
But in mid-summer and early fall, they plants need a little boost. I could scoop out more soil from the bottom of the compost bin, but it’s not ideal. At this point in the season my pots and raised beds don’t need more soil: they just need nutrients.
So, I could either buy a bottle of organic fertilizer, or I could brew up some home-grown goodness from my compost bin! Which would you choose?
Cup of Tea?
If you chose a homebrew over a store-bought bottle, you’re in luck. This easy process will save you a lot of money, and it’ll give your garden more access to consistent nutrients. Brewing your own compost tea will give you a sustainable, self sufficient garden full of healthy produce.
Compost tea isn’t the sort of tea you’d pour for your grandma if she came to visit. But your plants will drink it up in a flash and ask for more. Best of all, since you control the potency of your compost tea, they can have as much as they need.
Many tea-brewers choose to use diluted compost tea weekly in their gardens. This weekly application gives your plants consistent nutrition, instead of the “feast or famine” approach common to other liquid fertilizer types.
How Does it Work?
When you brew yourself a pot of herbal tea, the healing properties of the plant are infused into hot water. Then, you drink your tea, and those properties can get to work healing your body. The same goes for compost tea.
When you brew your plants a pot of compost tea, all the healthy microbes that live in the compost are infused into the water. This boost of nutrients and life-sustaining organisms revive the soil.
Soil dynamics can be complex: it’s never as simple as just feeding and watering. But compost tea—like our own herbal teas—can boost nutrients and fight off pathogens to keep your plants healthy.
Compost tea feeds the soil with nutrients and microbes that work with the plants to build a healthy garden. A garden that’s sipping compost tea regularly needs less water and minimal fertilizer compared to other gardens.
With compost tea, your garden will have stronger roots and healthier growth. Plants drinking compost tea regularly are also better able to absorb and retain nutrients. This means that they’re better at getting what they need from the soil and using it.
This tea is sounding pretty good, isn’t it? So how do you start brewing?
Brewing Up a Batch
Getting started with home-brewed liquid fertilizer can be as simple as steeping compost in water for 24 hours; or it can be a slightly more complex process.
The best compost tea is made by aerating the tea during steeping. This part of the process will brew a stronger, more microbe-rich liquid fertilizer. I’m going to give you a step-by-step guide to brewing aerated compost tea with an aquarium air pump. But don’t worry! If you don’t have a pump or just don’t feel like aerating, you can use this guide to brew non-aerated tea too.
Ready? Let’s get started.
What You’ll Need:
A Bucket & Water
Grab a five-gallon bucket and fill it with water. If you’re using tap water, you’ll need to let the bucket of water sit out, uncovered, overnight. Tap water is full of chemicals like chlorine and fluoride that need to dissipate before it can safely used as a base for liquid fertilizer.
If you use tap water without letting the added chemicals disperse, your compost tea won’t be full of helpful microbes. They’ll all be dead, instead. If you have a private well or are using fresh, spring water then you can use your water right away.
Aeration: If you’re aerating your compost tea, you’ll also need an aquarium air pump and an air stone.
Molasses: Many gardeners like to start with a small amount of un-sulphured, blackstrap molasses. This is because the natural sugars in molasses will boost the healthy bacteria content of your tea. About a 1/4 cup of molasses is standard, but you can go up to about 1/3 of a cup for bacteria-heavier tea.
A Tea Bag: Last of all you’ll need a cheesecloth, adult-sized sock, or one leg of old pantyhose filled with one gallon of dry compost.
Got it all? Great! Let’s get started.
Brewing Compost Tea Liquid Fertilizer
Add the molasses to your bucket of water. If you’re not going to be aerating your tea, just use a stick to mix up the water and molasses a bit to help it dissolve. Then, submerge your gallon of dry compost in the bucket of water and molasses.
Now, if you’re not aerating, you can just walk away and leave the compost to steep. You will want to come back a few times a day, over the next week to stir the brew gently as it steeps, but otherwise, just let it be. After the compost has steeped for a week, remove the bag and give your bucket one more good stir.
If you’re aerating your tea, attach the aquarium pump and the air stone right after submerging your compost. Follow the pump directions, turn it on, and leave it running during all 24 hours of tea steeping. After 24 hours, turn off the pump and remove the compost bag.
How Do I Know When it’s Done?
When compost tea is done brewing, it will have a rich, earthy scent. The smell is savory and not unpleasant. There should also be some foaming in your bucket. Non-aerated teas will foam much less than aerated teas. If you’ve aerated your tea, you’ll notice quite a lot of foaming at the top of your bucket. This is normal and healthy.
You shouldn’t smell any foul odors. If your smells like a trash can, don’t use it. Teas that smell noxious are likely home to a wide array of plant-harming pathogens.
Using Your Liquid Fertilizer
Now that you’ve brewed up 5 gallons of liquid fertilizer, what do you do with it?
You can use compost tea directly as a nutrient boost, or you can dilute it with non-chlorinated water for regular applications. If you’re diluting compost tea for regular applications, try mixing 2 parts water to 1 part tea. For a gentler application, 1 part tea to 5 parts water is also very effective.
Whether you’re using it diluted or undiluted, you can apply compost tea directly onto your plants as a drench. You can also apply it with a sprayer.
Additionally, hydroponic gardeners can add compost tea to their reservoirs. Mix about 1 or 2 quarts of compost tea to 10 gallons of reservoir water. But remember that if you are adding compost tea to a hydroponic reservoir, your system will need some sort of constant aeration. Stagnant compost tea will become a breeding ground for unhealthy bacteria.
Aerated compost tea should be used within 48 hours. This type of liquid fertilizer is more active and alive than non-aerated tea. This is good and bad. The bad part is that aerated compost tea has a very short shelf life.
Many tea brewers recommend dumping your unused tea back into the compost pile after 48 hours. It’s sad to see all that hard work seep back into the compost bin, but at least you know it isn’t wasted. You’re nourishing your compost pile for another batch later!
In contrast, non-aerated teas can last up to 6 days in a sealed, light-proof container. To help it last another day or two, you can aerated it on the 6th day. But after that, treat your tea as aerated compost tea and use it up quickly.
Remember that the benefits of compost tea depend primarily on the quality of the compost you’re using. If you start with bad compost, you’ll end up with bad tea. If your compost is just mediocre, your tea will be too.
Try to pick rich, healthy compost with plenty of worms in it. In addition, avoid filling your cheesecloth tea bag with partially composted garden waste. Go for the good stuff: your garden deserves the best.
Compost tea is a great way to treat your plants to a natural boost of energy. You love your garden, and you want it to thrive, so pour your plant a pot of this nutrient-dense tea.
They’ll enjoy the earthy, rich taste of liquid fertilizer, and you’ll enjoy the plant-building benefits. After all, there’s nothing more satisfying than seeing your garden thrive all around you, especially when you’ve done your part to help.
Go ahead, brew up a batch of compost tea. Drench your plants with it, then join them in the garden while they drink deep. Then brew up a pot of chamomile tea for yourself, and you and your plants can have a little tea party together. Sounds like fun to me!