I have a 12- or 14-year-old golden barrel cactus which (while in my possession for 10 years) has never bloomed. It seems healthy and has been repotted several times. It's now in potting soil. I've added a tiny amount of Osmocote to it over the years. What could be the issue?
It may be that it is not getting enough light or enough phosphorous. Check to make sure it is getting enough light (bright light) and give it some bone meal to help increase phosphorous. This article will help you as well:
More watering in spring can occasionally bring about flowering as well, though care should be taken not to overdo it, as this can also lead to root rot.
Why are the edges of my barrel cactus turning white?
This is typically caused by under watering or sun scald. While it is a cactus, it does need some water and if it has been drier or hotter than usual where you live, you may need to give it some supplemental water.
Sun scald typically happens with plants that are not use to the sun yet, such as a plant you just bought from the store and then set out in your garden. It is the sun burn or the plant world. It can also happen if you suddenly get a hotter, harsher day that you typically would have for that time of year. There is not much you can do for a plant once it has a scald, but they can normally recover from it on their own.
The cacti are about 32" tall and doing ok; is it good or bad for them to train the garden hose so water flows into the center interior? It seems to take quite a bit without overflowing.
While that should be fine, keep in mind that these plants require very little watering. They are native to arid desert regions and usually have only rainfall to supply their moisture needs. Therefore, only water your barrel cactus once a week in summer to avoid root rot.
I have a large barrel cactus and there are several "babies" growing out the side. Can these babies be removed? The best time of the year, and how is this done? Can the babies be transplanted?
Yes, they can be removed and grown. They are called pups. Here is an excellent article on how to remove them and propagate them:
We are moving from southern California, Zone 10 to Tehachapi, Zone 8. Have many potted cactus and succulents, can they survive there? Most importantly a potted 50+ year old barrel cactus with plantlets, can I plant this in the soil or do I need to keep it inside during the winter? I've searched the web and cannot find an answer.
Tehachapi is actually Zone 9 and yes, the cacti and succulents will be fine there. They need to be in well-draining, sandy soil when planted outdoors and should do fine over winter.
Soil mix for golden barrel cactus.
Yes. Everyone has their own 'recipe' for potting soil. If you talk to 10 growers, professional or amateur, you'll get at least 10 different recipes. You just need to get used to using one that works for you.
can i use the same mixture for replanting?
I use a commercial potting soil, containing peat moss, perlite, and finely ground pine bark. I add extra perlite. I've used this for almost 40 years when potting cactus and succulents, and I find it works great. Most cactus and succulents aren't super picky about soil as long as it drains really well.
I have had this golden barrel cactus for years and now it is starting to die. I don't think there is any saving it. It is caving in all around the bottom and spreading fast. I have seen these die with little ones that sprout on the dying one. How does that happen, as I would like to carry out the legacy?
Cacti can be infected with fatal fungal rots, and look perfectly normal for months. Then they start to collapse, as if a leak was letting all the air out, and proceed to collapse in a few days. If you had pups already sprouting, you could cut them off and root them, but if they're not already there, it's not likely they'll sprout from diseased tissue. You don't mention if the plant is potted or in the ground, but in either case the most likely cause of the collapse is too much moisture in the soil, or insufficient drainage of the soil. This article might help you with your next attempt: https://www.gardeningknowhow.com/ornamental/cacti-succulents/barrel-cactus/barrel-cactus-care.htm