Germination

Gardening to 'grow your own food' from square foot to half an acre !!
Post Reply
Freeranger
Legendary Laner
Posts: 3171
Joined: 17 Apr 2012, 10:13

Germination

Post by Freeranger »

Is there any rough rule of thumb for which seeds need light and which darkness? I don't know - big ones in the light, small in the dark. Or fruit light, veg dark etc?
I've put some old seeds to germinate but nothing's happened to most of them. I don't know if it's them or me!
User avatar
lancashire lass
Legendary Laner
Posts: 6527
Joined: 28 Jun 2007, 15:17

Re: Germination

Post by lancashire lass »

The tinier the seed, it most likely needs light (imagine a small seed with finite stored food trying to feed an emerging seedling - if it was buried, it would not have enough to sustain growth before reaching the surface and probably die) Also think of weed seeds on cleared ground - when the weeds and grasses are removed allowing more light to hit the soil surface, it usually results in an explosion of weed seedlings sprouting. Dig the soil over, and fresh seeds are then lifted up and able to germinate. Hence, light rather than moisture/warmth are more likely to break dormancy and trigger germination.

Bigger seeds that will have more food stored will be able to use it to push up to the surface, so they can be covered over and providing they are still viable and have optimum warmth and moisture, will germinate. Light here isn't so much an issue but that doesn't mean they will not germinate if the seed was on the soil surface - again, warmth and moisture are more likely to trigger germination (imagine how seeds are dispersed - birds and animals that eat fruit will deposit undamaged seeds in faeces so are already naturally buried, whereas something like peas and beans in dry pods are scattered on the surface, some will get buried under leaf litter but both covered and uncovered seeds will germinate in the right conditions)

As gardeners, we tend to grow a single seed at a time in individual pots/plugs to maximize the seeds potential unlike in the wild where a clump of seeds would germinate together where only the strongest / quickest / healthiest that can outgrow the others will be more successful. But the randomness of this method could go the other way especially in extreme conditions such as dry weather or poor soil fertility when the competition can also be their demise.

Now, how old is old seed? All seeds age and over time, viability drops (in year one you might get 100% germination, but year two maybe only 70% of the seed will germinate, year two only 40%) A small seed having less food available is more likely to lose viability much more quickly than say bigger seeds like beans - so something like celery (a very fine seed) or (notoriously bad for germination failure) parsnip are less likely to germinate after a couple of years whereas beans and most cabbage family (like broccoli, caulis, turnips) can have good viability up to 5 years. You can extend seed viability by storing them in a vacuum - air contains oxygen which is a radical and causes aging, so when it is removed the aging process is slowed. That's why when you buy seed in a sealed foil sachet, they are more likely to germinate than seed loose in a paper envelope. As soon as you open the sachet, place it in a small zip lock bag (and try to gently squeeze the air out as you close it), then the stored seed are more likely to survive longer for the next season.

Maybe this list of seed viability might be helpful.

EDIT - I noticed it lists lavender seed as having a viability of 1-3 years yet I once sowed seed over 10 years old that was stored in an unopened foil sachet (I forgot I had it and decided to see if they would germinate - I think nearly all of them did)
Freeranger
Legendary Laner
Posts: 3171
Joined: 17 Apr 2012, 10:13

Re: Germination

Post by Freeranger »

That's a really helpful answer, LL, thank you - and the link very much so.
I think I'd been thinking along the right lines, but was getting variable results. On reflection and in consideration of your answer, I think my problems are largely due to lack of warmth. I have moved trays into the car but am still having more success with the larger ones. I think I might ask Santa for a propagator this year.
My high hopes for the old pea seeds have come to nothing. Think I'll wash them in Milton and give them another try then ditch them all if no success. A shame as I have loads of old varieties of different veg that are much more interesting flavours and textures than many of the modern ones.
User avatar
billnorfolk
Legendary Laner
Posts: 1067
Joined: 07 Jul 2011, 13:24
Gender: Male
Location: Great Yarmouth Norfolk

Re: Germination

Post by billnorfolk »

Freeranger wrote:That's a really helpful answer, LL, thank you - and the link very much so.
I think I'd been thinking along the right lines, but was getting variable results. On reflection and in consideration of your answer, I think my problems are largely due to lack of warmth. I have moved trays into the car but am still having more success with the larger ones. I think I might ask Santa for a propagator this year.
My high hopes for the old pea seeds have come to nothing. Think I'll wash them in Milton and give them another try then ditch them all if no success. A shame as I have loads of old varieties of different veg that are much more interesting flavours and textures than many of the modern ones.

Thats an interesting post. All the seeds I have set this year are use before 2015 the last year I did much in my garden. Cabbage seeds 2 varieties, carrot 3 types, red beet, courgette , lettuce and leeks all have germinated apart from parsnips which I did buy new seeds just in case as think they need to be fairly new. I did order a few packets of seeds from Thompson & Morgan but after 2 weeks got fed up waiting so when ahead with the old seeds. I always store mine in a zip lock bag and an airtight container in an old fridge I have in the garage, surprised they germinated so well but they did. Got an old packet of sweetcorn going to pop in a tub with damp kitchen towel hopefully will germinate. Keep yourself safe.
A leek in the hand,is worth 2 in the roof.

Bill's Diaries.....2012 2013 2014
Freeranger
Legendary Laner
Posts: 3171
Joined: 17 Apr 2012, 10:13

Re: Germination

Post by Freeranger »

All the seeds I have set this year are use before 2015

Well that's annoying, Bill!
And encouraging too, I suppose, but I'm pleased for you that yours have worked.
I hadn't actually looked at how old the other things are, but actually they go back to 2011 growing season, so maybe I'm asking a bit much.
I still think the bigger ones might still work if I had them in different conditions. Our house is always cold as it's part renovated with holes and thick stone walls which means it lags behind outdoor temperatures. We're up a hillside in southern Scotland, so it's much colder and we're a good 4 weeks behind most of you.
I think it's possible that I soaked the peas for too long. I have some left so I'm going to try again for a shorter time and nick the skin, then do as you suggested with the sealed container but in the car.
I think maybe the compost isn't great either. It's quite coarse, so I'll try and find something to raddle it with to make it a bit finer.
On that point, another question if I may...
On a video I watched of carrot growing in pots, the guy raddled the compost then mixed in sand and powder BB&M as a fertiliser. 1) I only have building sand available 2) My BB&M is in pellet form. Question - can I get away with just raising pots up to improve the drainage, and using a liquid feed instead? Thanks for any advice.
User avatar
billnorfolk
Legendary Laner
Posts: 1067
Joined: 07 Jul 2011, 13:24
Gender: Male
Location: Great Yarmouth Norfolk

Re: Germination

Post by billnorfolk »

Freeranger wrote:
All the seeds I have set this year are use before 2015

Well that's annoying, Bill!
And encouraging too, I suppose, but I'm pleased for you that yours have worked.
I hadn't actually looked at how old the other things are, but actually they go back to 2011 growing season, so maybe I'm asking a bit much.
I still think the bigger ones might still work if I had them in different conditions. Our house is always cold as it's part renovated with holes and thick stone walls which means it lags behind outdoor temperatures. We're up a hillside in southern Scotland, so it's much colder and we're a good 4 weeks behind most of you.
I think it's possible that I soaked the peas for too long. I have some left so I'm going to try again for a shorter time and nick the skin, then do as you suggested with the sealed container but in the car.
I think maybe the compost isn't great either. It's quite coarse, so I'll try and find something to raddle it with to make it a bit finer.
On that point, another question if I may...
On a video I watched of carrot growing in pots, the guy raddled the compost then mixed in sand and powder BB&M as a fertiliser. 1) I only have building sand available 2) My BB&M is in pellet form. Question - can I get away with just raising pots up to improve the drainage, and using a liquid feed instead? Thanks for any advice.

Probably with seeds keeping cool and in air tight containers is the way I think might help to keep seeds over a few years. The soil in Norfolk is very light and sandy good for some things like Carrots but it soon drys out and needs constant feeding to give it body, hence the sand in the pots for carrot growing makes it easier for them to get some length in light sandy soil.Fertillizer I love liquid Fertillizer for my veggie ,if I use a chemical Fertillizer grow more tops my list ,but because of light soil must have some manure or well rotted compost. Sharp sand is the best to use it allows draining better than building sand which tends to be softer, used to use wind blow beach sand from our local beach mixing at 30 70 in favour of the compost .
A leek in the hand,is worth 2 in the roof.

Bill's Diaries.....2012 2013 2014
Freeranger
Legendary Laner
Posts: 3171
Joined: 17 Apr 2012, 10:13

Re: Germination

Post by Freeranger »

Thanks, Bill
Gwenoakes
Legendary Laner
Posts: 7325
Joined: 11 Aug 2007, 19:58

Re: Germination

Post by Gwenoakes »

That is interesting, Bill. My carrots if you can call them carrots have been a disaster over the last two years, very small and wobbly, but no carrot fly and they did taste nice after about three quarters of an hour cleaning them in all the nooks and crannies.
User avatar
billnorfolk
Legendary Laner
Posts: 1067
Joined: 07 Jul 2011, 13:24
Gender: Male
Location: Great Yarmouth Norfolk

Re: Germination

Post by billnorfolk »

Gwenoakes wrote:That is interesting, Bill. My carrots if you can call them carrots have been a disaster over the last two years, very small and wobbly, but no carrot fly and they did taste nice after about three quarters of an hour cleaning them in all the nooks and crannies.

Yes had some of them ,heavy clay soil is the worst for carrots ,lighter soil is better gives them a better chance to go down looking for moisture .A foot deep reach filled with a compost sharp sand mix will give you longer carrots.
A leek in the hand,is worth 2 in the roof.

Bill's Diaries.....2012 2013 2014
Gwenoakes
Legendary Laner
Posts: 7325
Joined: 11 Aug 2007, 19:58

Re: Germination

Post by Gwenoakes »

Thanks, Bill. Will try that but not this year as all my beds are planned out now.
AliSt
Learner Laner
Posts: 1
Joined: 30 Jul 2020, 15:33

Re: Germination

Post by AliSt »

Here are many helpful posts. Thank you so much!
Post Reply