I have a question that may seem banal, but it is not.
At what depth can reach the roots of the clematis, and what is the space they occupy in width?
thank in advance.
I think it would depend on the soil conditions and the specific type of clematis, but they have the potential to get very large. I once had to remove a well-established C. armandii and the roots easily penetrated down to 18" and spread to more than 8'. And some of them were very thick -- much like a large shrub's. Since I wasn't trying to save the plant, only remove it, I chopped through the roots to get the crown out and left the rest to decompose in the ground.
Thank you for your answer.
I'd like to know the difference between small-flowered hybrids, large-flowered hybrids and large climbing as Montana, orientalis and Armand.
I really do think that some clematis can reach a depth of 40" otherwise they would be all planted in pots.
What do you think about?
The larger the vine, the bigger the root system :-) However, most plants tend to have the bulk of their roots located in the top 12-16" of the soil - that is where the bulk of the soil moisture, nutrients and oxygen is located. In the larger scheme of things, very few plants produce deeply penetrating tap roots and those that do tend to do so in response to specific growing conditions, i.e. reaching down to underground aquifers in very arid climates. The vast majority of woody plants (and all vining clems are considered woodies) have relatively shallow but very widespread roots systems. The spread - not the depth - is why many clematis are restricted in their suitability for container growth.
And that's not say that these cannot be accommodated in containers for at least a short period of time. Container culture is a natural dwarfing situation because the root run IS so restricted - most container grown plants other than annuals and smaller perennials will never reach the same size as those grown in the ground. It is very similar to bonsai except that bonsai involves frequent root pruning and nearly constant top pruning to maintain size and health.
I dug up (to relocate) a three year old 'Princess Diana' in excellent soil and the rootball fit into a 2 gallon pot.
The rootball of a 3 year old 'Durandii' fit into two 1 gallon pots (I divided it)
The rootball of a 5 year old 'Ville de Lyon' in hard clay soil fit into a 2 gallon pot.
I shovel pruned a tangutica that was 3 in excellent soil and the roots extended less than 18" wide and 12" deep. A second one 'Grace' was a lot smaller and fell apart to the point that it died.
I may not have gotted every single root but I did get the bulk of them.
I recently read that viticella and vigorous large flowered types can have their roots go down as far as 4 ft. Last autumn, I had dug up large plants of 'Huldine' and 'Ville de Lyon' these had been in their new location for only two years, both had very thick congested root systems of about 20 x 20 inches ... though, with many roots penetrating below and into the harder subsoil, it took a real effort to dig and lift these big heavy buggers out, gggrrr! I originally dug the site down to a depth of 30 inches, though then went another spade depth and incorporated more manure and peat moss. These clems will now enjoy very good soil amended to an extreme depth ... either I will have killed them with kindness, or they'll go totally nuts! It's often suggested to dig to a depth of 18" x 18" and even as little as 12" x 12" ... this is okay if good soil exists beyond this region, though not so ideal if heavy clay is present.
Thank you all for your extensive replies.