Excuse me for the little bit strange question
I started a collection of cactus all from seeds, then grafted on Heliecereus , i grafted in shoots from big heleio then i cut the stock to put it in smaller pots, by doing so the growth rate degraded badly,
anyway the cut stock re produced roots and filled its pots as appear in pictures, is it necessary to put in bigger pots to get a better growth rate ?
I don't want to do so to keep the ratio between the plant size and pot size, can i just use a fertilizer instead ?
Repotting necessity
Re: Repotting necessity
The only real reason for re-potting is if the plant body grows too much for the size of the pot, if the soil gets toxic from a build up of salts, or if the soil becomes exhausted. If the third is the case you can fertilise to replace the nutrients the soil lacks instead.
Regarding grafting, as you found out, the shorter the stock generally the slower growth since there is less photosynthesizing material below the scion. I have seen plants grafted on the top of six foot high Cerei that grow at a very rapid rate. The problem is left too long they may also grow very much larger than in nature and so quite out of character. I once saw a slide show of a Dutch collection where Sulcorebutias's were all grafted on around four foot high Cerei and were now clumps about ten inches to twelve inches across and looked ridiculous since they were a size they would never attain in nature, therefore were completely out of character. I suppose you have to make a judgement with vigorous grafts as to when the plant is large enough to cut down and not let it get too large to be out of character.
However from a general view of manageability and room we tend to grow on shorter stocks, or cut them shorter as you have done later. However leaving them on the longest stock possible for as long as possible will usually produce the maximum growth in the shortest possible time, provided you don't let them get too large and out of character.
Regarding grafting, as you found out, the shorter the stock generally the slower growth since there is less photosynthesizing material below the scion. I have seen plants grafted on the top of six foot high Cerei that grow at a very rapid rate. The problem is left too long they may also grow very much larger than in nature and so quite out of character. I once saw a slide show of a Dutch collection where Sulcorebutias's were all grafted on around four foot high Cerei and were now clumps about ten inches to twelve inches across and looked ridiculous since they were a size they would never attain in nature, therefore were completely out of character. I suppose you have to make a judgement with vigorous grafts as to when the plant is large enough to cut down and not let it get too large to be out of character.
However from a general view of manageability and room we tend to grow on shorter stocks, or cut them shorter as you have done later. However leaving them on the longest stock possible for as long as possible will usually produce the maximum growth in the shortest possible time, provided you don't let them get too large and out of character.