Thermal stratification of store-bought fruit

As mentioned elsewhere, I’m trying some experiments with starting fruit plants (specifically, bushes and trees) from the seeds of store-bought fruit.

Since it’s too early in the season for US-grown apples and pears to be ready for harvest, whatever such fruit is available in the stores right now would have been harvested last year and keep in cool storage until recently. One would think then that they ought to have received whatever thermal stratification they’d need in order to be ready to sprout and grow.

Over the past weeks I’ve been paying attention to what the labels on fruit say about its origin and have been putting aside seeds sorted by the cultivar they came from and where they were grown. Most apples and pears are from the US and I’ve been putting them in pots, with each pot used for a single cultivar. Seeds from Southern Hemisphere growers (e.g., New Zealand, Argentina) have been going into the fridge for chilling before getting pulled out some time in the future as I would assume those were recently harvested and haven’t been chilled (or at least not all that much).

While it’s very early in this experiment, it seems that yes, US-grown fruit has been sufficiently thermally stratified in cold storage to germinate and grow when planted and watered.

Right now I have perhaps five types of baby apples and I’m hoping the other half dozen or so types I planted will also show activity pretty soon.


I’ve got 15 Fuji seedlings…in a flat and growing…
.and something in the refrigerator with white roots and stems 2 inches long! A couple weeks or three since I ate an apple and put the seeds in a baggie and put them in refrigerator.

Do foreign grown seeds germinate? From what I heard, they probably won’t since imported produce to the United States has been radiated. Guess you could experiment.

IIRC, foreign grown produce has not normally been irradiated.

While some produce is irradiated with the intention of killing bacteria on it, my understanding is that it’s actually few and far between and is marked as such. If you’re buying irradiated produce, you’ll know it.

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Plant your apple seeds and see what happens.

Most fruits are not irradiated, smile. I have two Abate Fetel seedling pears growing
that were product of Italy, I think. They were grocery store fruits, like yours.
Since they have already made one winter, I think they got lucky in the genetic shuffle.

For anyone interested, here’s an update on the seeds planted from store-bought fruit.

Some of the apples had germinated and started growing. Some didn’t seem to be doing anything and had me a bit concerned.

As time goes on, more seem to be sprouting. I think this is because some apples sat on a shelf at room temperature for a while before I ate them and saved the seeds, while others sat in the fridge until eaten. The ones that were warmer for longer are probably the ones coming up the fastest.

Of course it could also be that some types have a higher germination rate than others and some don’t need as much time at warm temperatures before they become active. (Of course they aren’t genetically identical to the mother tree so they won’t all behave exactly the same. Nevertheless, they ought to be much more similar than a bunch of randomly selected apple seeds.) Statistical variation is also a factor too.

So the moral of the story is if you’re getting concerned about slow germination of store-bought fruit that ought to have been thermally stratified, it may yet happen and just need more time.