when do you know plants are dormant ?

@hi2u_uk then why buy a columnar tree? It is clear from its name that it was going to grow up and not out and just a modicum of research, not to mention info given here, would confirm that shortening it will change its growth pattern and thus shape and fruiting.

Having it in a pot so small it keeps falling over looks even more daft than having a tall plant in a suitable pot with enough root space and compost to keep it healthy and upright.

 

@Obelix-Vendee, the information from the RHS posted by @NigelJ states that the leader should be cut back.

 

if i remember correctly its in a mix of soil and peat free multipurpose compost. A picture will have to wait as im away from home until next week though ive picked most of the fruit . The fruit is mainly on spurs off the trunk not on the branches if i remember correctly.

This is an interesting instruction though as i said earlier the fruit isnt on the side branches that i want to cut . I was going to leave the ones that had fruit this year but the length of these is small.

It was advertised as a patio apple tree . The first i'm hearing of columnar trees is from this forum so when i looked at pictures of columnar trees online i just assumed thats what it is.

As i say my view is that the tree is too big for the pot not the other way round which is what you are suggesting. It has not always fell over it just seems to have grown tall this year. Also I dont understand why a garden centre advertises something as a patio apple tree but then expects you to put it in a 100Litre plant pot. To me thats not a patio plant

 

A 100 L pot is only a 50cm cube (2 ft cube).
You could put it in a heavier pot; I have Dahlias in both plastic and terracotta pots out front and the terracotta ones don't blow over, but the plastic ones do; so the plastic ones are stood between the terracotta ones. These plants are in a 50:50 mix of soil and compost.
You should expect the tree to reach 6 to 8ft in height.

 

I think you will find even dwarf plants continue to grow, they just grow slower in most cases, I'm not sure any plant will stop growing until it dies.
Admittedly trees do reach a certain size in general before going into decline.

Personally I'd have pruned any new stems, coming from the main stem, back to a couple of buds in August.
If it's too tall I'd cut the leader back as well, but if you do it in the winter it may just put out more vigorous shoots next year.

I may be wrong, but to be honest what have you got to lose.

Just don't cut off any shoots that have fruiting spurs unless you are prepared to lose some fruit next year.

 

Even dwarf conifers don't stay small. They just grow slowly. Over 10 years they may stay small but over 20 or 30 they'll get rather large. Garden centres are there to sell you plants.

As for pot size, I wouldn't grow a rose in less than a 60cm pot so it's a bit much to expect an apple tree to be OK in something smaller.

 

I have several roses in 30cm pots and they are doing fine. I also have two dwarf conifers bought 8 years ago which have barely grown more than an inch and are still less than 12 " high and wide. However they were bought from a specialist conifer nursery.

 

It really depends on the plant and the conditions it's growing in.
There are some very slow growing conifers, but you need to find a specialist nursery. I know of one near RHS Rosemoor. Dwarf species Rhododendrons can grow no more than 6 to 12 in in height in a rockery, but finding them is the problem.
However the question here is about an apple tree.

 

It is @NigelJ but growth patterns are not written in stone so comparisons can help.

The OP clearly doesn't want to increase the pot size so he's going to prune anyway and will then find out if it was a good idea or not.

 

I've always experimented, usually read the book but rarely follow it to the letter .

Sometimes you win sometimes you don't but lots of plants are forgiving and most haven't read the book.

 

I need to be clear that although its an apple tree its an apple tree grafted onto something else. My understanding is that this is done do that the apple tree doesnt grow into the size of a 100% apple tree

 

Yes nearly every apple tree you see is grafted onto varying rootstocks that control the growth and size the tree is likely to reach.

Even so, they rarely reach a certain size and then stop, some pruning is usually done.

 

If you are unable/unwilling to use a larger pot for your apple, why not return it to the place you bought it from and ask them to explain exactly what they sold you and how you should deal with it ? The impression given is that you chose the wrong plant for your site and conditions ( an easy mistake to make ) and are looking for a miracle cure.
Returning to the original question posed, I rather think you can tell that plants are dormant/approaching dormancy when you catch them yawning ( tho they could just be bored I suppose ).

 

This is interesting and maybe worth another post under a separate heading, i only buy plants online as i dont live near any plant retailers and normally want specific species of plants that meet my requirement. I dont just buy any old apple tree. I have never returned a plant though sometimes they have been a bit disappointing . Do people return plants bought online ?

Whenever i have contacted a retailer for advice they never seem to be that helpful so i very rarely do this. I'm always very skeptical about whether they send what they advertise and think there should be some sort of genetic testing facility because i feel they could just slap a label onto any apple tree and say its x or y species with certain characteristics and who would know. This is a conversation i've had often and hope that with AI and advancing more accessible tech it will happen.

Also i cant even find the email receipt so im not 100% sure what it is or where i bought it from. Ive been searching ever since i made this posting. I've had it for about 2-3 years now and as i have said it has grown so would it be accepted as a return ??? . Theres no way it will fit in a box . Im interested to understand how and when people return unsatisfactory plants but i feel this is another topic

The impression i was trying to give is that i want to prune it which i think is a normal thing to do for plants. I'm just trying to understand when is the best time to do it ie how i will know its dormant. Its performance has been very good compared with some of my other plants

 

TBH it probably wont matter if its dormant or not, the sap will not be rising at this time of the year.