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Why Acid-Loving Crops Thrive at pH 5.5 in Hydroponics · Hydroponics Daily

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  Hello, hello, hello. Welcome back to Hydroponics Daily, your go-to podcast for
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  everything soilless cultivation.
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  I'm your host, Dr. Russell Sharp, the founder of Utrema Ltd.
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  And today is a short and sweet episode because I've spent six hours driving
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  in the car to get to York and then spend a full day at a conference,
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  presenting at a conference on regenerative agriculture.
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  And now I'm back home and I am very, very tired.
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  But I do want to do a podcast and I do want to do one on an interesting subject,
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  and that is, I was thinking in the car on the way back, what are the most acidic
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  types of crops, and are they grown in acidic conditions?
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  Conditions if they're grown hydroponically so there
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  are a number of crops that grow in acidic soils most most famously cranberry
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  so that in the soil range is the optimum is 4.0 to 5.5 but there's it grows
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  in acidic bogs normally and famously but there are other crops so blueberries.
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  Same genus i think family 4.0 to
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  5.0 4.0 to 5.0 so
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  even more acidic than cranberry but there are other ones so
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  cassava staple of many developing countries
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  that's from 4.0 to 6.5 so a
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  big range there but also both sweet potato and normal potato fairly acidic pineapple
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  fairly acidic 4.5 to 5.5 and tea as well camellia sinensis 4.5 to 5.5 so you
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  might think when you put them into hydroponics,
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  you need to mimic these conditions. However, that's not the case.
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  Blueberries are widely grown hydroponically.
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  A place like Morocco, massive blueberry farms, Ukraine,
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  and they're all grown in cocoa or some other inert media, and it's hydroponic
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  feed, but it's normally, it's often targeted at 5.0 to 5.5.
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  So basically at the lower end of the sweet spot.
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  5.5 is still there. So.
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  Slightly higher you'd say of their preferred pH which is 4.0 it's actually you
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  know a lot higher because it's a logarithmic scale so that's interesting again
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  with cranberries higher than the bog level pH tea pineapple all much higher and that's because,
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  it's the optimum conditions in soil are often a lot lower than in than in the
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  hydroponic solution because in soil it's about nutrient availability,
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  but also microbial activity,
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  toxicity of elements like aluminium, and the buffering of organic matter and clays.
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  Whereas in hydroponics, it's about solubility and keeping everything from precipitating
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  out and avoiding any damage, direct damage to the roots.
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  So the other, but the real main
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  reason is that to get all those nutrients available, you would have to.
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  Create a very bespoke fertilizer that
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  was specific to that crop and actually
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  fertilizer companies don't want to do that and when you
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  can get away perfectly well with a 5.0 to
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  6.0 hydroponic feed there's no real need to produce one that's 4.0 because the
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  yields and the health qualities of the blueberries and the cranberries they're
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  perfectly adequate in when they when they're grown at 5.5 so why would you need
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  to only you would need to if you had some sort of,
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  water source that was very acidic but even if
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  you did you'd probably find other problems with that like you would get a lot
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  of heavy metals in the water so you'd probably want to clean that up and neutralize
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  it and clean up the water so blueberries very commonly grown hydroponically
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  cranberries still very much widely wild cultivated.
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  That's hard for me to say.
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  Tea, again, it's grown in soil. There's no major...
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  Effort to grow it hydroponically however my former
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  phd student ridian he's welsh and he is
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  growing different species and different types of
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  tea and to make different blends of
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  tea different species of camellia i think
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  it's called dragon something dragon is the
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  name of his new company so that would be really interesting maybe he'll grow
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  them hydroponically he is he was an early adopter
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  of hydroponics before even i've grown plants
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  in hydroponics again pineapple unless hawaii
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  has some big issues with the soil beyond what
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  they've got at the moment they're not going to be grown and yes we've
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  grown potatoes sweet potatoes in hydroponics
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  but they don't need really acidic conditions so there's
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  your answer that's they're the most acidic loving crops and
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  but they are not grown in extremely acidic they're
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  the most acid loving crops should i say but they're
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  not grown in very acidic hydroponics when
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  they're grown hydroponically they're grown in what's still
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  within the sweet spot for hydroponics 5.5 so there you go let's see if that's
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  the case for alkaline loving plants tomorrow in tomorrow's episode the technical
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  term them for an acid-loving plant in gardening is ericaceous because lots of
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  them are in the Erica family, the Heather family or the rhododendron family.
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  But the actual scientific name is calcifuge, which means a refugee from calcium.
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  Whereas tomorrow we're going to talk about the plants that love calcium and
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  love high pH, the calcicoles.
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  Yeah, until then, thank you very much for listening and goodbye.