Latest / Hydroponics Daily / Seed 'Vigour' vs. 'Viability' - why it is crucial to know the difference

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Seed 'Vigour' vs. 'Viability' - why it is crucial to know the difference · Hydroponics Daily

• 0:00
  Hello there and welcome back to
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  Hydroponics Daily, your go-to podcast for everything soilless cultivation.
• 0:07
  I'm your host, Dr. Russell Sharp. I'm the inventor of gold leaf,
• 0:12
  as it's known in the US, or liquid gold here in the UK, plus many,
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  many other products used in hydroponics, sports turf and arable,
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  but that's enough blowing my own trumpet.
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  Do you know the difference between seed vigour and seed viability.
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  Two very important variables. If you don't know the difference,
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  don't worry. That's what this podcast is going to go into.
• 0:34
  If you're more of a beginner, I suggest you look at some of the earlier episodes of Hydroponics Daily.
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  And I found out today that Apple Podcasts only show the last 100 episodes.
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  So if you go on to podbean
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  and look for hydroponic daily podbean that's where
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  we host the podcast and there you'll
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  find all of the podcast episodes
• 1:00
  running back to january the first of this year i've done one every day of 2025
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  2025 and hopefully every day of 2025 i will be doing an episode that is my that
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  was my new year's resolution and i've stuck to it and it's now the fourth of
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  july so we've got most of the way through the year.
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  Happy 4th of July to everyone in the United States of America.
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  Have some Boston tea on us limeys over here.
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  We won't be taxing you too hard, metaphorically or literally, in today's episode.
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  It's just seed of vigour and seed of viability.
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  Often these are used interchangeably, but they are completely different.
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  So the terms sound similar, but they describe very different qualities. So let's get into it.
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  Seed viability refers to whether a seed is alive and capable of germination
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  under optimal conditions.
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  It's a yes-no status. Can this seed sprout if everything is perfect?
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  Now, a seed can be viable and you still might not be able to germinate it. That's up to your skill.
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  The seed viability is predetermined and depends on how you store it.
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  Seed vigour is very different, and that's about how well the seed performs once
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  you've germinated it, how fast it grows, how uniformly it germinates,
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  how strong it is, and how does it establish in less than ideal conditions.
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  Think amount of plant, stress resistance,
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  emerging strength, root development, these are all vigor okay
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  so you want it to be viable and vigorous when
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  you buy seeds so imagine two batches
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  of basil seeds may both be 95% viable but
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  one with higher vigor will produce more consistent faster
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  germinating seeds crucial in an automated hydroponic system where days to harvest
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  is absolutely critical so i've the reason i'm doing this episode now is because
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  i have purchased some seeds off the internet and they were a rare strain,
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  a completely different species that's normally grown.
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  And so they were in the seed bank and they said, you know, we assure certain amounts of viability.
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  And sure enough, the seeds were viable. And this species you could store for
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  many, many years and they still be viable.
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  However, so about 80% germinated. But the problem was they had terrible vigor.
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  And one of them got mildew straight out of the bat, which is not great.
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  So there must have been some mildew spores in there or gray mold or something
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  like that. It was covered in fungal growth anyway.
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  And then about six of them just keeled over and died at the slightest inconvenience.
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  And then only one of them survived.
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  And even that.
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  Wanted to die at every opportunity
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  and really was trying to get
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  me to put it out of its misery you know slightly too much
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  i gave them all a dose of salicylic acid
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  to try and boost them and it just went no and scorched the
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  leaves because whereas all my other plants that were
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  growing with different varieties and strains they they
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  were growing perfectly well and they just loved the salicylic acid
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  so the vigor was terrible and
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  the reason why i think is because you've got
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  to remember when any organism is growing
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  the cells are repairing themselves if they
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  get mutated the genome can repair itself and the damage to the cell structures
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  can repair itself seeds are dormant and so they're not cells actively dividing
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  they're not growing so they're not actively repairing themselves they're not
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  metabolizing so any ionizing radiation like gamma rays x-rays.
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  Any sort of radiation coming in would
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  be mutating that and also mutations
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  happen due to chemicals and just through
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  time so these seeds have clearly just lost
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  their vigor now the plants are starting to recover and
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  the bigger they get i think the cells start to repair themselves and
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  hopefully if i can get seeds off this plant i can i can
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  renew them and the seeds will certainly not be as
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  damaged and i can select to the healthiest plants
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  from them so i had no whereas before i've bought seeds and they've all none
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  of them have germinated and clearly this wasn't a vigor issue this was a viability
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  issue so seed quality is is determined by both of those things whereas seed
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  companies when you're buying seeds off the internet they normally only ever.
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  Guarantee viability so watch
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  out for that you might want to ask how long have those seeds been stored
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  for because that's going to be critical about how healthy
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  they get but then sometimes you might be looking for mutants
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  anyway lots of plant people look for novel interesting phenotypes
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  and genotypes and they're looking for
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  unusual growth types and so you might want old seeds for
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  that purpose you know the chinese send pumpkin seeds
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  up into space to get them mutated because
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  they believe that the mutants can grow better than the wild types
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  so yeah i don't
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  know any hydroponic growers that are sending their seeds into space you
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  could get one of those balloons that you know
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  put them put like webcams into near space
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  and or you could expose them to some if you
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  had a good source of electromagnetic radioactive waste.
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  Near you you could put some seeds near there you know
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  so yeah that's interesting i mean if you're
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  in the eastern europe if you're in ukraine belarus put
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  some seeds in the chernobyl exclusion zones see if
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  they grow more interesting however if you grow something
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  like basil lettuce coriander you want
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  absolutely rapid vigour so lettuce
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  basil and coriander they they can decline rapidly in
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  storage tomatoes and peppers are renowned
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  for their good storage over years many decades tomatoes.
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  Can last decades in storage rocket and arugula
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  is that coriander in the uk uh notorious for fast
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  fast vigour loss even in good storage so that's
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  something to consider how to store seeds affect
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  how storage conditions affect
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  seed viability and vigor the three main enemies are
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  heat humidity and oxygen so seed long
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  longevity is maximized both the vigor and
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  the viability by keeping them cold ideally between one
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  and 10 degrees celsius if you're an amateur grower so that's
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  fridge refrigerator you can do frozen storage
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  but you do need to look into that because
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  there's a lot that there's a lot that goes into it you need
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  to get them dry around 30 to 40 percent humidity dark place
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  sealed containers oxygen exposure increases respiration so and one rule of thumb
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  for all you americans on the 4th of july the sum of temperature in fahrenheit
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  and relative humidity in percentage should be less than 100 that doesn't really
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  work in in metric does it in celsius or kelvin so you're.
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  Keep that one to you know just for just for america
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  that one we don't know i don't know what it would be in celsius maybe that someone
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  can work that one out and come up with a handy tool for seed storage so how
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  could it if you have poor viability and germination uniformity and timing low
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  vigor causes uneven germination poor poor tray performance in things like.
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  Microgreens delayed growth so you could get bottlenecks in
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  rotation systems say you have a mother room
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  where you just germinate seeds on the room no
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  a germination room sorry if you grow and say auto flowers
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  and auto flowering species you could
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  have a seed germination room and then a vegetative
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  veg room and then a flowering room this could if you
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  had seeds that were low vigor this
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  could really upset how long it takes to run through all these
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  different rooms weak roots you're going to have
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  transplant shock nutrient issues damage and
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  things like this and a pest and disease that could get in through the
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  root system and you're going to be your yields
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  will be far lower than you know the full potential of
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  a healthy wild type plant so especially
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  critical in automated nft raft systems and commercial
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  microgreen growers in nft you're going
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  to get things like algae growing away quicker than you
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  can control them and then in an already weakened root
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  system use of peroxides and things like this will damage the
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  root system even worse in a low vigor low
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  health plant so how can you test
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  for viability and vigor so for
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  viability is just a germination test place 100 seeds if you've got them obviously
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  you can't do that if they're a very valuable seed or a rare one but things like
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  wheat you know they place 100 seeds on moist paper in a warm place and count
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  how many sprout in five to ten days that's a good test of viability how many can germinate.
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  You can also cut the seed in half and stain them with a dye that only turns red if the seed is alive.
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  However, it's a bit more technical. Best to just do a germination test.
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  I've forgotten what the name of that chemical is. It's a pink dye.
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  Let me pause this and see if I can find it. Okay.
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  Tetrazoleum. Of course it is, Russell. Tetrazoleum, that's the pink dye,
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  you can cut a seed open, see if it's viable by, are the cells alive in there?
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  So that will say whether it can germinate, not whether you've got the skills to,
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  get it to germinate. For vigor, there's a couple of tests you can do.
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  You could do a cold test, soak seeds and germinate them at 10 to 15 degrees Celsius.
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  Slow and uneven emergence in those slightly stressful conditions will suggest low vigor.
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  And you could do an accelerated aging test, expose the seeds to high humidity
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  and temperature for three to five days, then test their germination.
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  So that's how you could test them. So yeah, interesting that you can test with
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  both. So how can you prevent low viability and low vigor?
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  Well, always buy your seeds from a reputable supplier ask them
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  how long they've been in storage that will be crucial for vigor label all
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  seed containers with the date and crop lots that they were
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  harvested at if you're storing your own seeds store the
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  seeds in optimal conditions so low temperature low humidity and
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  low oxygen avoid bulk buying sensitive crops
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  unless you can store them properly use older
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  seeds for non-critical runs or trials and use
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  new seeds for high value crops and
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  high value situations and consider priming or
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  pelleting for uniformity these are more common
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  in asia you get pelleted seeds i don't
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  think it does involve plastic polymers as well so a lot of people would
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  want to avoid pelleting priming involves
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  giving them a treatment that will sort
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  of get them halfway to germination first or it
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  could mean like seed coating them with a chemical that promotes germination on
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  the eutreema website there is a blog post
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  talks about the plant the chemicals that you can apply
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  to seeds to improve their germination there's about a list of
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  about 30 that i put together from various scientific papers it's
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  one of our most read web pages
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  on our website so if you just go into the blog section of.
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  Eutrema and type seed germination that will come up
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  and you can look at all the different chemicals that do that things like nitrates all
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  the hormones things like that if you're struggling to find eutrema it's
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  just the latin word for wasabi e-u-t-r-e-m-a.co.uk very
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  popular web page that for some reason loads of people go
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  on to that every day some some a
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  few sacks facts about seeds to wrap it up before we go
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  some seeds can last decades lotus seeds over
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  a thousand years old have been germinated and
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  loads of seeds in the british museum i think or the naturalist museum when there's
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  a bomb in the second world war and stored for centuries germinated one of the
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  bombs hit and it was raining and all the seeds germinated pelleted seeds may
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  look fancy but they're more sensitive to moisture and time apparently.
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  But I say they're more common. I bought a lot of brassica cabbage seeds from
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  Korea and they all came in fancy coloured pellets.
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  Older seeds sometimes produce mutations or uneven phenotypes, especially in hybrids.
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  That's something that you might be looking forward to. So the journey from seed
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  to harvest starts long before the roots hit water.
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  Understanding vigour, viability and storage is key to planning efficiency,
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  reliable hydroponic productions.
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  And remember strong seeds equal strong systems so if
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  you are if you are looking for strong plants always check how long they've
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  been stored and you might want to choose a different variety or strain if
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  they've been stored for a long time even if they are you know
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  much much sought out after genetics the
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  good news is that if you're using a fertilizer like
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  gold leaf or liquid gold it's got very low electrical conductivity
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  so it will help when seeds are germinating
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  they won't have to struggle to get water in and you can
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  go from seed to harvest of your crop with
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  just that one input and water you don't
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  need grow media necessarily you don't need to
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  add anything else cal mags ph ups ph downs
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  dechlorinators pk boosts you can go
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  the whole way with just that one bottle of gold leaf or in
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  the uk liquid gold if you want any questions or any
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  more information then you know where to find me at utreema.co.uk
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  so if you'd like to know anything else or
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  you think i've got anything wrong then please do email me love to talk to people
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  who've listened to the podcast we've had a few emails in from people who've
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  appreciated listening and have asked for advice even people asking for advice
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  on other people's products other people's fertilizer and i'm more than happy
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  to do that i just like talking to people about growing plants because i'm a.
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  Plant nerd want of a better word right i am off and i'm gonna go and watch some
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  television boring night tonight okay i'll see you tomorrow it's the weekend
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  it's a freaking weekend have some fun goodbye.