18 month colt growth

Please.forgive me as I am not a breeder so knowledge on growth is fairly limited.

I have an 18 month colt, full warmblood. He is tiny, currently sticks 14.3hh at the withers and just under 15hh in the bum.

We did a fairly inaccurate string test the other day and it appeared to give is 15.3-16.1hh, which is what I was hoping for. It was done with stretchy tape and it was really not accurate so wanted to retry today with bindertwine that wouldn’t stretch (I did follow contours). When I tried again with a more accurate measurimg device from mid knee to coronet band and got 15 inches!

  • edited to say I finally Re string tested and it did give about 16 inches. I must have been drinking that day lol!

No, I have had pretty good luck with the general rule of- they normally grow about two hands after they are 12 months old and 1 hand after they are 24months old. I think you are fine. He may just have very short cannons… Or you may not have measured properly?

Both sire and dam were 16.2+ and I was hoping for a smaller warmblood in the 15.2 to 16hh range, 15hh will likely be too small![/QUOTE]

That’s the problem with breeding, it is not an exact science.
That’s why breeding should mainly be left to good breeders. You can’t just breed in hope it will be X, Y, Z. It is, IMMHO, way cheaper to just buy one already on the ground that matches most of the criteria. But anyway… I’m sure you’ll take great care of that youngster even if he tops at 15hh.

Do you know what type of babies this stallion usually produce?
Do you know what type of babies this mare usually produce?
Have they been reproduced in the past? What was the outcome?

Make sure your horse is followed by a good vet/nutritionist in case he might be missing something that would prevent normal growth.
Or next time the vet comes, ask him to predict your colt’s height.

No horse is fully mature until at least 6-7 years of age so your horse has a lot of time left to grow.

14.2hh at 18 months should mature to at least 15.2hh or more depending on the lines (some lines just take a long time to mature). I have one nine year old mare that stopped growing between her 4-5th year but shot up an inch and a half on her 6th birthday-I was shocked.

I feel like I did purchase this one from a good breeder. They said he was smaller than anticipated, and would be smaller than the parents. He was the first from the mare, and the stallion has many foals on the ground both here and Europe, from the ones I have seen average 16-17hh.

He was not backyard bred, and we all know it’s not an exact science. Breeder said linely max 16hh and that’s what I was wanting. He was just purchased a few weeks ago. He is branded hanoverian with grannus and rio Grande lines.

I was more concerned about the string test saying 15hh, when he is already close to that height. I had never heard of a yearling growing only 1 - 1.5" at final height?! Thought I measured pretty accurate but will maybe need a 3rd go at it!

He was well cared for, in good health and has a stunning personality. Vet had no concerns upon castration. I think the mare just doesn’t produce large babies (her last filly is on the smaller side too) which worked out for me, as I was ideally hoping for one 15.2-16hh. Of course even if he is 15hh I will love him, I just may squish him!

Look at the brightside… if he only turns out 15.0 and you were hoping for 15.2, he will be a measly 2 inches too short. The good news is at 2 inches too short he will not suddenly be a tiny little pony that you will squish. Now if you were hoping for a 17.2 beast and he was only going to be 15.0 then I’d be worried.

The way you are doing the string test sounds different then the way I was taught. I was shown elbow to fetlock. Holding string on the elbow, swivel the string 180 degree holding your fingers on the string where the fetlock was. That is the projected wither. 2" post 18 months is not right unless its a pony.


The elbow to ergot, then turn the string and go elbow to withers to get the final height has always proven to be the most accurate estimate of eventual height IMO. But you are doing it too young, 18 months is too young. You need to wait until the lower growth plates are closed before it is going to be anywhere near accurate, which is “usually” about 24 months, but can vary up to 30 months or so for late maturing slow growing breeds (breeds that have not been specifically bred and fed for fast growth and early maturity and strength). The system works by the fact that the lower growth plates close first, and the higher growth plates close later. So give it at LEAST another 6 months before doing this test. Give it 10 months to be even more accurate. Note, the inaccuracy in this test often comes in in identifying the exact point of the elbow, then in keeping the string there through the turn of the string.

String thing.[URL=“https://www.horseloversmath.com/estimate-mature-horse-height/”]

Growth rate chart 0-2yrs;

I have not found the string test to be all that accurate - so don’t worry about it! I HAVE seen 2 year olds that only put on one or two inches, and I’ve also had FOUR year olds put on 2 inches. I find it more accurate to look at the horse, and if they look really finished and balanced between 18 months and 2 years old, they are probably going to be smaller. If they are gangly and unbalanced, they will be one that puts on a lot of growth.

Thanks all! He is somewhat between solid and gangly. Just sticked him again and his bum is 15hh and withers 14.3 and this time did it all on level ground. He has a nice wide chest, and in good body condition. I think he will end up short and round, but makes me feel better that he will likely go over 15hh since he is almost there already. I will try the other string test tomorrow, realizing it may not be accurate due to his age.

My gelding took till 6 to reach 16 1/2. Biggest growth spurt was at 4 1/2.
My 3 year old filly is 16.1 h (with really long legs) and I got her cheaper because she was very small at 6 months.
I bet your boy will be 16 or possibly over.
And top breeders have size ranges in offspring. That is just how is goes with Wb’s.

I only have the one experience but I got my now 5 y.o. right at 18 mos. He was about 14.3 at the time. He now sticks at 16.1 and looks like he might be growing a bit more as we speak… So I wouldn’t worry too much at this point.

Heck, my WB boy was barely 14h as a 2yo and by 4yo he was a full 16.1. His string test predicted around 15.2. Horses are weird, they’ll break all the rules we can come up with :lol:

Hope your guy ends up being exactly the horse you’re dreaming he’ll be! I bet he grows quite a bit more when all’s said and done.

I think we need to see pictures to give you our most accurate guesses as to his final height.

My part WB had a growth spurt at 7 years. Grew 1 1/4 inches. Never did the string test.

Can we make a date in March 2020 for an update? :slight_smile:

I have stood by Rio Grand - he is enormous - well over 17.00 because I have a 17 hh mare and he is way bigger.

Some warmbloods take along time to mature - even if this one is shorter than you planned, if he is ‘round’, his barrel will take up your leg???!!!

Everyone is right…warmbloods seem to take forever to reach full height. One thing I do know. Don’t look at the height of the parents. Go back one generation to the grand sires and dam’s . It will give you a MUCH more accurate basis for the type and height of the “grand foal” at maturity.

I have a gelding who will be 7 in May and JUST had a growth spurt. He grew about half an inch in the last month or two. He is now 17.1 and has finally leveled out. He has been in light work for the last few years because he was still so bum high (and is generally a big, long legged horse) that he could not balance himself.

I also have a coming 4 year old who has grown very little over the last year. He is currently 16 hands, and looks very mature and balanced. I think he will likely top out there. He is already more coordinated and has better proprioceptive awareness than the big guy did at 6 1/2.

You never know, especially with warmblood breeds. I think this makes it particularly important not to have rigid expectations of growth or achievement of developmental markers (e.g., readiness to begin training) by a certain age.

I only have the one experience but I got my now 5 y.o. right at 18 mos. He was about 14.3 at the time. He now sticks at 16.1 and looks like he might be growing a bit more as we speak… So I wouldn’t worry too much at this point.[/QUOTE]


My mare was short enough that at 5’1" I could easily see over her back when I bought her at 2 1/2. Last year at 5 at her inspection she was just under 16 hh. Now I suspect she’s more like 16.1 given the difference between top of my head and her withers. I keep asking her to stop growing, but she’s butt high again…

sigh I keep asking her to stop growing, [/QUOTE]

My friend’s 4yrs old gelding is 17h2… He’s having another growth spurt at the moment…

When I started training (early 5yrs old) my mare she was about 16- tiny 16h1 and had been that size for quite a while and then suddenly around 7yrs, I realised she had reached a solid 16h3 close to 17… that wasn’t necessary!

After that she became wider in her chest/shoulder and it now matches her fat (muscled) ass!