Old seed viability

[Plant Pimp]

A friend gave me some old 'San Pedro' and 'Peyote' seeds that had been given to him over a year ago (maybe 2). Is there a chance that any of these seeds still might be viable? I'll try to sprout them anyway, but the last time I tried to grow cacti from seed my germination rate was only 10% (I think they weren't warm enough).

Anyone tried to germinate old seed before? Hearing about your success or failure would be appreciated.

[Gunter]

I think it is relative to how old the seed is and how it was stored. I have grown seed that had a very low germination rate. I suspect this was because of age or storage.

Sometimes with older seed it is viable but takes longer to germinate. Axenic conditions are then ideal, also gibberellic acid might increase and hasten germination in these cases.

[Flip]

I would not worry about the seed being old.

Not every year has enough rain for seeds to germinate

cacti have a long evolution behind them and will have

adapted for such conditions -some will have survived.

But this really depends on other outside factors

regarding how they we're stored and such.

laying around on the sunny dashboard of a car is not one of them.

[Gunter]

I have found fresh seed to germinate 100% in 3 days, but some old seed have less than a 3% germination rate, this is unfortunate because I have purchased seed from one of my favorite growers and seed suppliers that has given me very poor rates and the same species purchased in the same year has also given others the same extremely poor germination rates, though when the seed was fresh it was reported very viable.

The seed suppliers make no guarantee of germination, but when you buy 6 packets of seed and all but one packet gives you 80%+ germination rate, and that lone packet gives you 3% germiantion rates (over an 8 week period) chances are that the problem lies in the seed.

Opuntia seed is good at lasting, but Trichocereus seed does not seem to store well and I have no scientific information to support the idea that it undergoes reversible dormancy.

Many growers report that older seed loses viability, I would suggest planting it within 3 years. In my personal experience Trichocereus seed much older than this does not grow well at all, though cold storage mage extend this. I have taken to making double orders of older seed to make up for this, though with older seed that still means less than 5 seeds out of 100 will grow.

[ 19. July 2005, 02:34: Message edited by: Archaea ]

[Plant Pimp]

Thanks for the info.

They may have been stored for up to 3 years in a desk drawer, so I guess if any germinate I should be happy.

[Gunter]

You might get quite a few to germ, always try.

[trucha]

The seeds are the culprits many times. Traces of sugar from the fruit can feed rot organisms and sometimes the seeds are erratically viable to start with. Sometimes these are self produced and sterile.

Its commonly claimed that people have gotten good germination on cactus seeds 10 or 20 years old.

Not my results at all although I have never had any troubles with 3 year old seed.

I have also had new seedlings come up in old seed flats for up to 5 years.

A warm water soak for 20 minutes might be of use for older seeds.

However, Cannabis seeds drop in viabiity rapidly too yet one single seed was discovered last year that HAD to be somewhere between 10-15 years old and stored at room temperature for the whole duration.

It was in such an odd place that it had to have been placed there for being exceptional so it was given to a friend and it sprouted within a couple of days.

One common problem with old seeds is that the plant they produce often show a lack of vigor.

Better to plant them though than it is to compost them!

[Gunter]

Ahh so my misfortunes have little to do with the age of the seeds.

Nice to know!

[trucha]

If you live in an area that permits it do a large scale planting using the screen covered box approach recommended by Mesa Garden.

Plant as heavily as you have seed.

G3 Gibberlic acid treament is said to work wonders too but I have only used G3 pretreated seeds rather than doing direct comparisons.

[Gunter]

I move to an area where they may be grown outdoor with a little cold protection on some colder winter nights. I think I can even sow them in the ground.

But we shall see... in about a week I might add.