Soooo, since they are sown, I should not water them until they sprout? or should I mist them to keep the humidity up in the ziplok bag? I know not to drench them in water, so that is not going to happen, but even if this does not work, I will start later on this spring when the conditions are better.
Thanks.
Getting seeds from buds
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Phatbowler
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Phatbowler
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Dalesmicro
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- Location: Toluca, Mexico
How does one know when cacti fruit are ripe?
I am taking pictures of cacti, including seeds. I suspect that for comparison, seeds should be ripe. If you plant it and it grows, it was obviously ripe, but from what I have read on this post, out of a batch of seeds some will sprout and others won't. So even if only some grow a guess I could count the batch ripe. Is there any other way?
I agree, most ripe fruits fall off either by themselves or a light push or pull, but I marked some fruit on the Ixtapan de la Sal Opuntia I photographed and almost 2 years latter 90% of the fruits I marked are still there, just as green as they were when I first marked them. Curious to see if they had seeds I cut one off (yes, I had to cut it off!). When I opened it it was reddish inside and had hard seeds. I have planted some to see if they grow.
While not mentioned in this topic (but in some more recent posts), I was wondering if treating the seeds with sulfuric acid (to simulate going through an animals stomach)might increase germination. If they don't sprout soon, I may try the sulfuric acid approach.
I agree, most ripe fruits fall off either by themselves or a light push or pull, but I marked some fruit on the Ixtapan de la Sal Opuntia I photographed and almost 2 years latter 90% of the fruits I marked are still there, just as green as they were when I first marked them. Curious to see if they had seeds I cut one off (yes, I had to cut it off!). When I opened it it was reddish inside and had hard seeds. I have planted some to see if they grow.
While not mentioned in this topic (but in some more recent posts), I was wondering if treating the seeds with sulfuric acid (to simulate going through an animals stomach)might increase germination. If they don't sprout soon, I may try the sulfuric acid approach.
Ripe fruit doesn't necessarily fall from the plant. Many cactus fruits break open one way or another and release seeds, either wholesale or almost individually. Some are set so the seeds will fall, others just sit there waiting for an ant or perhaps a violent rainstorm. Others remain embedded in pulpy fruit which can take months or even years before it dries out. Hopefully something eats at least part of it.
The majority (excluding Opuntias) of ripe cactus seeds can germinate at a moderate to high rate almost immediately that they are released from the fruit. All that is required is moisture, (usually) light, and a suitable temperature.
A minority will not germinate well or at all until a certain period passes, typically a few months to a year or two. Good examples are found among Ferocactus, some of which have zero germination for a year or more, then good germination. This sort of dormancy isn't always easy to spot and obviously not every species has been specifically tested for it. In some cases it isn't clear whether a short after-ripening period is best just considered as the seed being harvested too early.
Probably an even smaller minority have tough coats which are resistant either to water soaking in or to the embryo breaking out. I can only think of Echinocactus and Pediocactus, possibly there are more. The seed coat is weakened slowly by environmental processes, mechanical abrasion, temperature fluctuations, possibly freezing and thawing, and results in extended erratic germination leading to a seed bank.
In Opuntias, tough seed coats are probably the rule rather than the exception. Relatively few Opuntias in the widest sense seem to germinate well straight off the plant. Acids or other "violent" treatments can be used to artificially tough seed coats and lead to more consistent germination.
All these mechanisms and more in detail are fairly well described and documented. A good (advanced) place to start is Cactus seed germination: a review, although papers continue to be published. Usually though, a general idea of the temperature needed and whether there is likely to be any dormancy is all you nede to grow the things.
The majority (excluding Opuntias) of ripe cactus seeds can germinate at a moderate to high rate almost immediately that they are released from the fruit. All that is required is moisture, (usually) light, and a suitable temperature.
A minority will not germinate well or at all until a certain period passes, typically a few months to a year or two. Good examples are found among Ferocactus, some of which have zero germination for a year or more, then good germination. This sort of dormancy isn't always easy to spot and obviously not every species has been specifically tested for it. In some cases it isn't clear whether a short after-ripening period is best just considered as the seed being harvested too early.
Probably an even smaller minority have tough coats which are resistant either to water soaking in or to the embryo breaking out. I can only think of Echinocactus and Pediocactus, possibly there are more. The seed coat is weakened slowly by environmental processes, mechanical abrasion, temperature fluctuations, possibly freezing and thawing, and results in extended erratic germination leading to a seed bank.
In Opuntias, tough seed coats are probably the rule rather than the exception. Relatively few Opuntias in the widest sense seem to germinate well straight off the plant. Acids or other "violent" treatments can be used to artificially tough seed coats and lead to more consistent germination.
All these mechanisms and more in detail are fairly well described and documented. A good (advanced) place to start is Cactus seed germination: a review, although papers continue to be published. Usually though, a general idea of the temperature needed and whether there is likely to be any dormancy is all you nede to grow the things.
--ian