Hi, I've seen some videos that make simple compost tea feed. Some just use compost and water, some also use molasses and an air-stone bubbler. I was wondering if this is a complete feed for the plants (macro and micro nutrients), or does this kind of tea still require other sources of nutrient? Let's say I feed a tomato or pepper plant in a container with this, am I likely to still see any deficiencies throughout the life cycle?
You'll see less in the way of deficiencies, but teas are a rather weak source of nutrients. If you want to keep a heavy feeder like a tomato producing through the peak of the season, I would be surprised if you could do it with just compost tea. Maybe if it was planted on a hugelbed that had a good store of nutrients under the roots, but on marginal soil I think you are going to have to mulch as well.
When I add compost tea to potted plants, it doesn't give them a flush of growth like Miracle-Gro does. Which is probably good. A flush of growth from a chemical fertilizer is not as desirable, because when the chemical is depleted, the plant returns to being hungry and growth stops. What's better is to mulch the plants along with the dose of compost tea. The growth that results from that combination is longer lasting and the plant is healthier, not just putting on a flush of green. My best potted tomatoes and peppers have about an inch of wood chips as mulch.
I think it depends on what the compost is made out of......a compost derived from a variety of organic matter will contain most macro and micro nutrients. If you are really concerned then I would say add a mineralizer like rock dust to the pot prior to planting.
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