Deciduous tendency of A. caput-medusae

[Magi]

Hello,
haven't posted here in a while.
In 2018 I sowed these Astrophytum caput-medusae.
Today, I can't seem to keep the tubercle count at greater than 3. Some of these are almost nothing but bald tap roots. Any idea how to keep the older tubercles from dehydrating and eventually falling off? Thanks!

[Stuart]

Nicely grown seedlings, my plants, grafted on Ferocactus Glaucescens have always been deciduous. I expect the same happens in habitat and all the plant's energy is stored in the root.
Stuart

[KarlR]

In my experience they are quite thirsty plants. I've never had any grafted ones, but none of mine have ever been deciduous. They do tend to lose older tubercles, but I think the older they get the more tubercles they can keep alive at the same time. But they do need quite a bit of water.

[Ali Baba]

In my experience they are quite thirsty plants. I've never had any grafted ones, but none of mine have ever been deciduous. They do tend to lose older tubercles, but I think the older they get the more tubercles they can keep alive at the same time. But they do need quite a bit of water.

Agreed they certainly suffer if not watered earlier in the season than the norm. Check for thrips too, they can cause die back even at low levels of infestation

[Magi]

Thank you all!, I'll be potting them on in the next few days (once the roots have cured) where they'll have more available moisture, hope that'll improve the issue.

[Tina]

Magi,
You are still doing better than me to raise these from seed, I have 2 plants that I haven't killed yet, they live in my hot GH & get a little water thru the year but ATM I feel its luck not any skill.
As long as you are keeping them growing & the roots are expanding you are doing really well.

[Terry S.]

I am a self-confessed Digitostigma murderer. It is such a distinctive species that I really want to grow it, but have killed most of the seedlings that I have bought. I have now actually kept a plant growing in my collection for the best part of two years by doing the opposite to that suggested above. It is growing in a clay pot such that it has less moisture available than the other cacti in my greenhouse. Apart from the tendency to be permanently deciduous, the tubercles have not died back except for a few of the very oldest ones. The bottom line on this is that we all have different growing conditions and with these difficult plants we just have to experiment.

[KarlR]

I sowed mine in 2013 and they have been grown in a pure mineral mix since they were first pricked out. They're in square plastic pots together with all the other plants. They get the same treatment more or less, just a bit more water.

I suspect they would appreciate even more water than I give them, perhaps like Leuchtenbergia.

[MaciejW]

I have read it somewhere (might have been on this very forum) that they enjoy under-bench position and some water all year round. A good sized seedling which I bought in autumn 2017, stays away from the direct light and was given some water even during the winter (very sparsely and only during warmer spells). Thanks to that, a bud that developed late last year, survived all winter and is now nearly ready to bloom.

[Ali Baba]

Mine are in full sun and are kept dry in winter. They form buds all year round but only the ones that start in the spring and summer flower.