What’s Brewing is a podcast all about compost tea hosted by Troy Hinke.
Troy Hinke served as Rodale’s Compost Research Specialist alongside the founder of Soil Foodweb Inc., Dr. Elaine Ingham. Troy now runs Living Roots Compost Tea, where he offers several services including consultations, compost sprays, and compost brewing, among others.
Episode seven of a 10-episode series on compost teas, host Troy Hinke talks about the many ways we can make use of the biology in our compost teas.
When is the Best Time to Use Compost Tea? (01:23)
The first place we can apply compost tea is at seeding, either through soaking or at planting. For most plants, especially annuals, the next application will be at the first true leaf, and then at one and two months later.
For most established lawns and landscapes, doing 3-4 annual sprays will do the plants well. A more frequent monthly application will also greatly benefit the plants.
Another application would be during signs of pest or disease. If the threat is too great, it’s best to treat the problem first using some type of organic solution. But note that using pesticides or disinfectants will most likely get rid of the good biology on the plant surfaces, so it’s good to come back and apply compost tea after treatment to get good microorganisms back on the plant surfaces.
The next application compost tea can be used in is for prevention. For plants prone to fungal infections like tomatoes and roses in the late summer, applying compost tea once every one to two weeks can help shore up their immunity against fungal infections by acting as a shield of sorts.
Can You Put Too Much Compost Tea? (03:52)
While there is sure to be a level at which applying compost tea is no longer advantageous or may be detrimental, there is yet to be research done on the topic at the time of the podcast. That said, most growers don’t have much time in their schedules to make and apply too much compost tea to really overdo it.
How Much Compost Tea Should We Use? (04:43)
For regular plants, a good application density would be 5 gallons per acre. For taller plants like trees, one gallon per one foot of tree height per acre will do. For example, if you have 10ft. tall trees, you’ll need 10 gallons of compost tea per acre.
Application Methods (05:15)
The method of application most people will use with compost tea will be either spraying or watering. Anything used for watering or applying liquid fertilizer can be used for compost tea, including watering cans, backpack sprayer, spray rigs with tanks, ATVs with sprayers. The important thing to remember about applying compost tea is to apply it as evenly as possible over the target area.
“There’s a solution to apply compost tea on basically any scale. Sometimes it just takes some creative thinking as to how you’re going to do that.”Troy Hinke
When applying compost tea using sprayers and nozzles, nozzles should be larger than 400micrometers. If you can see through the nozzle or applicator with your naked eye, and we’re working with microscopic organisms, then that microscopic organism will definitely be able to fit through that hole.
There are many types of sprayers, from handheld sprayers similar in appearance to paint sprayers, to Tommy gun-like sprayers. While they all look pretty cool, a simple sprayer on a garden hose will do the job.
When working in larger scales, you’ll be dealing with gas-powered water pumps. Diaphragm pumps will work better as opposed to piston pumps, the reason being piston pumps move so fast that they grab onto the compost tea so hard that they damage the microorganisms in them.
Lastly, you can also use root injectors for the compost tea. When using root injectors, an application rate of 10 gallons per tree will work well for trees 15ft. and higher, while smaller trees will require less.
Additional Ingredients (15:01)
Some people add in additional ingredients to the sprays. It’s important to note that when adding microbial foods such as humic acid and fish hydrolysate to the compost tea spray to keep it minimal to avoid any stubborn residues on the container’s walls.
And as previously discussed in the last episode, if you’re planning on adding mycorrhizal spores and/or Azomite to the compost tea, add them after running the tea through a second filter to avoid losing any product because more often than not, they’ll just get mixed in with the other sediments and thrown away.
If you’re applying compost tea to heavy feeders that require additional nutrients from blood meal, bone meal, crab meal, and the like, you can add minimal amounts of that after brewing and filtering.
Seed Soaking (20:00)
When thinking of doing seed soaking, you can use extract because first, it’s much faster to use extract; and two, as you’re working with tiny seeds, they don’t need a whole ton of biology on them right away.
You can soak your seeds anywhere from a quick dip up to 24 hours, but you have to realize that some seeds will soften. And if you’re using seeders like an Earthway seeder or a Jang planter, it’ll be difficult to run soft seeds through those, which means you’re going to have to think about the logistics behind soaking the seeds and them letting them dry.
On the other hand, if you prefer using starts rather than seeds, and you want to get some good biology going for them, you can give your starts a quick dunk in compost tea as you’re planting.
So, if you’re out in the field with your tray of starts and a bucket of compost tea next to you, you can simply grab a start, dip it in the bucket, and then stick it in the hole. That way, you’re incorporating good microorganisms from the compost tea onto those roots and onto the plant.
Compost Tea in Drip Irrigation? (23:29)
One question often asked is using drip irrigation for compost tea. Many people add compost tea to a drip irrigation tank, and it’s an excellent way to get microorganisms working with plants, but it would be better to use extract instead.
If you’re planning on sending out compost extract through drip tape, remember that residue from the compost tea—the sticky microbial foods, most especially—will sit in the tape and possibly create a biofilm that could go anaerobic. Because of that, it’s better to use extract, no microbial foods, sticky residue.
That said, when using extract, remember to flush the drip tape with water afterwards!
Compost Tea on Sprouts and Microgreens (25:25)
Using compost tea on sprouts and microgreens is an excellent way to provide more nutrients and minerals to the seedlings, which then results in more nutrient-dense crops.
When planning on using compost tea on sprouts and microgreens, be careful not to soak any seeds or sprouts in a compost solution for too long without aerating as it will turn anaerobic and become detrimental to your crops.
Other Compost Tea Applications (26:07)
Cut Flowers. Another way to make use of the biology in compost tea or extract is to add a tiny amount in cut flower arrangements to make them last longer—you just have to make sure to change out the water with the compost tea or extract every 12-24 hours.
Hydroponics. One other practical way of applying compost tea is through hydroponics. A few years back, there was much talk of allowing hydroponics to come on board as certified organic by USDA standards, and many people who have been in the organics movement for a long time argue that organic-certified crops need to be truly soil-based and not grown in any type of water solution.
Using compost tea in hydroponics rather than synthetic nutrients solutions means we are using those same soil microorganisms to provide plants with nutrients, micronutrients, and minerals that they need as if they were grown in the soil. To Troy, this meets the argument of soil-based growing because we are using soil microorganisms to grow plants.
Soil Remediation. An interesting application of compost tea is soil remediation from an overload of amendments such as manure.
Compost Accelerator. Troy adds extra compost tea to his compost pile and the material in the pile breaks down exponentially faster with the added tea.
If you have compost that is not breaking down due to a lack of biology, or if you’ve got compost that has gone aerobic, you can break down the pile and spray all the materials with compost tea to get beneficial aerobic biology back on the surfaces.
“There are a number of ways that compost tea and compost extract can be used. You just have to be creative.”Troy Hinke