Grafted cactus

[Newton]

Hi
Please excuse my lack of knowledge in this respect. I would like to learn more.

What happens typically to grafted cactus

1 Do they tend to survive for long or are they more temperamental than being grown in their own root systems.

2 Some of the cactus I have seen grafted onto rootstock is lacking chlorophyll with bright skin colours. What happens to these? Do they still survive and thrive on the rootstock.

3 As they age does the rootstock take over or does the grafted plant (the type usually on top) continue to grow and eventually develop it's own root system.

4 Are they worth the time money and effort to keep or are they just gimmicky type of plants cheaply marketed for a quick buck. A bit like some of the cactus in the market that have dried flowers superglued onto the body

Thanks
Chas

[gemhunter178]

The answer to your questions are much more complicated than I have expertise in. Mainly, all the answers depend on what the scion (grafted plant) and the stock (plant being grafted on) are.

For example, some grafts are temporary, while some can be permanent and span the entire life of the scion. Temporary stocks general include Pereskiopsis or Hylocereus and are generally meant to either keep a chlorophyll-deficient plant alive for a time, or, more commonly, to speed up growth on a massive scale. Permanent stocks such as Harrisia, some Opuntia and many other large columnars can also be used to speed up growth, but, in many cases, the plant will not need to be degrafted/regrafted unless the grower chooses to.

Hanazono would probably provide a much more comprehensive answer, but, here's my expereince:
As an added note, I use "rootstock" and "stock" interchangeably.

1, typically, grafts will be easier to grow and the scion will grow faster than on its own roots. For how long they last, it depends on the choice of stock (and sometimes scion, as certain cryptocarp Mammillaria have a higher chance of spontaneously dying from drying out when grafted), also see above on my comment on temporary/permanent rootstock. You could create grafts that do the opposite by selecting a hard-to-grow stock and grafting something very plain and common on top of it, but you will almost never see this unless the grafter is trying to prove the point that almost any cactus can be grafted.

2, Cacti lacking chlorophyll can live just fine on the rootstock as long as the stock can continue to produce enough energy for the two plants. The most common ones seen in stores is a Gymnocalycium on a Hylocereus (that we sometimes call a "lollipop"). Typically, these don't last long as one or both parts of the graft will tend to dry up or rot within an year or two, but, with some careful regrafting, you could make both parts of the graft survive just fine. These plants are honestly a good choice to practice your own grafts if you see them on sale. A note that these chlorophyll-lacking plants will always need to be grafted onto something as they cannot produce their own sugars/energy. If the stock dies, the scion will need to be regrafted or it will die.*
*Not-fully chlorophyll-lacking plants may be able to survive on it's own roots, depending on the level of vaiegation.

3, Once again, this depends on the species involved in the graft. Typically, without intervention, most grafts will remain reliant on the stock for roots, but, anything else (such as performing photosynthesis) can be performed as long as chlorophyll is present. A rootstock that causes the scion to grow roots sometimes is Opunita humifusa. Source: https://www.cactus-art.biz/technics/Gra ... istics.htm

4, Grafts are a much more varied topic than just "glued on straw flowers." Even the most gimmicky version of grafting (IMHO, those "lollipops" I mentioned earlier) have their own merit - they are actual plants that have not been mistreated by paint or those awful straw flowers. It can be argued that they could be grafted to a much better rootstock to live longer, and that is where the gimmick lies - Hylocereus grafts do not tend to live long, and most people buying them are not equipped to keep them alive past a few years at best... then we get some requests on why their colorful plant is dying and we cannot do much about it unless they are willing to learn how to regraft it.
Otherwise, it comes down to opinion - there are some people who are "own-root only" and refuse to buy grafted plants on principle. (There is nothing wrong with this stance, just noting some people prefer it this way), meanwhile, for the rest of us, grafting could provide a way for one to keep hard-to-grow plants alive easier, speed up growth on cacti that would typically take years to grow to the same size on their own roots, or bring a plant faster to flowering for breeding. It all comes down to how much of that natural/cost balance you want to take (grafted plants of the same size are typically cheaper.)

Oh on an added note, some grafts will make the scion grow fast enough that it produces a somewhat unnatural look - one that someone with a trained eye can easily tell apart from own-root plants. On one hand, this can produce plants not typically seen naturally, such as a multi-headed Ariocarpus kotschoubeyanus, but, on the other hand, some people do not like that look as it is different from the typical, more-natural look.

[Newton]

Thank you so much for your time and informative answer
It has answered most of what I need to know
I just need to establish now what this rootstock is as it's the one used by most nurseries here
Importantly is it likely to need regrafting in 12 months or so

[greenknight]

Looks like Hylocereus root stock. they won't be long-lived. Many of those plants don't need to be grafted, they've done this to get large plants quickly no doubt. You could de-graft and root those, or make cuttings from offsets. See: http://www.cactiguide.com/forum/viewtop ... 22&t=34104

<edit>When testing that link, I found the older photos don't work now. There are newer ones later in the thread that do work, though, skip ahead to see demonstrations of the technique.

[gemhunter178]

Not quite sure about Hylocereus on those, but, probably that or a related "jungle" cacti (Maybe Selenicereus?)
I agree with Spence though, many of the cacti pictured are rather easy to grow on their own roots - you could probably just root them, and, if you do, the stock may survive too by growing normally.

Edit, just read the message you sent, but, we also kind of answered it above: I would assume these stocks are more on the temporary side, and will need rooting/regrafting in a while.

[Newton]

Thanks gemhunter and green knight
My situation is that I am only here for a variable few weeks a year and de grafting requires a bit of ongoing maintenance until the plant is established etc
I dont think it's going to be possible to do this with the limited time I have.
This occasion lockdown has forced me to remain longer than anticipated.