"Bowling Pin" type growth in Echinopsis sp.

[sobriquet]

Hi all.

As a reative neophyte to growing the columnar cacti, I've noticed that at least one of my San Pedro's has a case of growing like a bowling pin in that the new growth is considerably thinner than the base.

Does this growth pattern result in permanent difference of diameter between different sections or do the thinner areas thicken up over time?

In the one I've noticed; it has been a newly rooted pup that has had a sudden boost of water etc.

The other ones are getting moderate water and nutrients and all appear to be growing at similar diameters to their bases.

[nothinghead]

I had an e. scopulicola which was shaped something like an hourglass when it was small (around 12cm) and as it grew the difference in thickness between the thicker "head" and thinner "neck" has evened out almost to the point of the entire length of cactus being the same thickness. Generally my observation has been that the thinner sections will fatten up with age.

[apothecary]

Usually happens if they lose a bit more energy than they had stored when producing roots, or it can also happen if their lighting changes (i.e. less lighting = thinner growth).

[Fugushi]

By "Bowling pin" do you mean something like this ?

If so it seems to be what tip cuttings do when they are developing roots. The less roots they have, the thinner they grow?

I was going to post a similar thread to this, asking wether this could be prevented.

Two more pics for an example of how they grow, 2 paches that seem to have had it when they were younger, and a bridgesii that has started doing it when the roots had just appeared.

And then a pic of the same bridgesii a lil while later. It had been in sun atleast 6hrs a day. Possibly more.

So can this be stopped ? Or is it just a part of taking tip cuttings ?

[M S Smith]

That sort of growth is mild etiolation due to lowered light levels during periods when the air temperature is still high enough to produce growth. The fact that it didn't yellow shows that it isn't full etiolation, but this sort of growth will scar the aesthetics a bit. I have not generally observed this "pinch mark" growing out, but when I have it is on larger plants where this pinch needs to harden up to support the upper sections of the column.

One of the nice things about living in an area with a very cold winter is that the plants are sent into full dormancy quite quickly when the cool weather hits in Oct. in the northern hemisphere. They then kick back into growth come late April as the temps rise just as rapidly as they cooled. If your plants are brought under artificial lighting in the winter, and then outdoor seasonal light in the spring and summer, you can easily get this sort of growth. It is a bit less common on plants in the ground that get a more consistent amount of light the years round.

I used to bring some plants indoors for the winter, but even room temps would produce the thin yellow tip growth of etiolation. And if they were on a window ledge they would wouldn't yellow, but they would get the thin growth from inadequate light. Now my plants all stay in the unheated attached garage and in full dormancy.

Here is just a small portion of my plants in the garage quite a few years ago. If you look closely enough you can see some of the seasonal pinch marks, but usually I've been able to limit them. It's sort of an art to tell you the truth. Saddly I only have 5 months to have them outdoors, generally from the end of April to the middle of October. I'd leave them out a tad more if I could but by then it's too cool to get growth and so I shuffle them in to prevent the soil from getting too wet before I am forced by the frost to bring them in. They sleep more than they are awake.

The second picture is better example of the pinching (or lack of it), as well as to show what sort of growth I can get in 5 month. Needless to say, fertilizing is a must in small pots, but I actually don't do it much and when plants get this big you better, otherwise the growth slows considerable.

~Michael~