If you own a youngster, or are looking at breeding your own, one of the most often asked questions is ‘how big will my horse grow?’ This can be important for a number of reasons, not least of which is whether they’ll be able to do the job you have in mind for them. This could be riding, driving, or breeding, or something else. However, some competitions have height limits, and all Breed Societies have recognised height requirements for their studbooks.
The size of the Dam and Sire will likely determine the size of the offspring. Sometimes however, offspring surprise the owners by either growing too much, or too little, possibly a throwback from earlier in their genetic heritage. The String Test is a useful tool and can be used (from a year) even when you don’t know your horse’s breeding.
This article should give you the information I wish I’d had before buying a youngster with no recorded breeding….
Why is height important?
The expected adult height of your horse can be important if you’ve bought a youngster to bring on or to make a certain height. Fatty was sold as likely to make 14.2hh….she is now (as of date of writing) 5 years old and is very unlikely to make 13.3hh. In fact I’d be surprised if she will mature to 13.2hh. For myself this isn’t too much of a problem, but this doesn’t stop me crossing my fingers before I look in the field every morning, just in case she’s had a miraculous growth spurt!
Height is important if you know that you need an equine that is above 15hh. It may be because you are tall, it may be because you need something that can happily carry a little more weight. It could simply be that you want a big horse, or a horse of a particular breed, or for a particular sport. Each and every one of the reasons is justified, and there will be a horse or pony out there that’s right for you.
How tall will my pony get?
An equine is considered to be a pony if it measures 14.2hh or smaller. However, there are caveats to this. A Falabella, or an American miniature horse, is always a horse even though it normally measures under 32 inches. Conversely, a Connemara pony is still a pony even when it grows above 14.2hh. However, breeding from an oversized pony of any breed is generally frowned upon as Breed Societies wish to maintain the heritage and type of breed for future generations.
If you know the parents of your pony you should already have an indication of your pony’s likely height. It will often, but not always, be somewhere between the two heights. So if dad is 14hh, and mum is 13hh, your pony will probably fall somewhere in the middle.
If you don’t know your pony’s breeding, but they are over a year old, you could try the String Test to get an idea of their likely adult height. Keep reading to find out how….
How tall will my horse be?
Horses are similar to ponies in that they won’t normally reach their adult height until around 6 years of age, although they may muscle up more after this. Draft horses such as Shires may take a little longer, but will have reached their full height by 8 years old.
Knowing your horse’s breeding will help you guesstimate their adult height, as will knowing the heights of any full brothers and sisters if they have any.
A good rule of thumb to go by is ‘add 2 hands to a yearling and 1 hand to a 2 year old.’ This doesn’t often go far wrong.
Will my cob grow any higher?
If your cob is over 6 years old it is most likely that you’ll get more width but no more height. By 6 years old the skeleton will have finished forming, and whilst muscle mass may make it appear that your horse has grown, it would be very rare.
How much more will a 2 year old grow?
A 2 year old that has been well fed and nurtured will already be 95% of its adult height in most cases. Early gelding may well increase the growth rate of some horses, but this isn’t scientifically proven.
If you measure your 2 year old and add 1 hand (4 inches), you won’t be far away from the adult height measurement.
Will a 4 year old grow much more?
A 4 year old may grow a few inches, especially if they are bum high. Be careful making this assumption though as gypsy cobs/vanners are quite often known to be bum high throughout their entire life!
If you’ve taken on an undernourished rescue, with correct care, even at 4 you may notice a decent amount of growth slowly over a year or so.
Some horses and ponies though are simply here to surprise us. There are many people ready to tell you how their horse grew 2 hands after 4 years old etc. This may very well be true. But don’t hang your heart on your horse having any sudden spurt, simply enjoy and appreciate the horse you already own.
If you haven’t already, use the String Test to let you know if your horse has any more growing to do.
How to do a string test
There are two ways to perform a string test. It only take a minute to do each, so try both and see if they give the same result….
1st Way
- Tie your horse securely so that it’s head isn’t too low
- Take a piece of string/baler twine and measure from the ergot to elbow
- Keep hold of the higher point and move the string from the ergot to finish in a line above the wither
- Note how far above the wither the string ends
- This is the adult height of your horse
The second way is even easier…
2nd Way
- Tie your horse securely
- Using a tape measure take the measurement between the coronet band and the centre of the knee
- Note the length in inches
- If your tape measure shows 13” your horse will be 13hh, if it shows 14” your horse will be 14hh and so on
Neither measure is infallible, and should only be used as a guide on horses over a year old. It is however a useful indicator, especially if you don’t know the sire and dam of your pony.
How do I measure my horse?
If you have a horse measure stick, this is the easiest and most accurate way of measuring your horse.
Before taking a measurement;
- Make sure that you stand your horse on level ground
- Your horse should be stood square and not resting a leg
- Your horse’s head should not be lowered, or held too high
- Measure to the top of the withers and record
If you don’t have access to a measuring stick, you could try using a tape measure, but it’s incredibly tricky to do this with any accuracy.
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Conclusion
You horse’s genetics will play the biggest part in how big your horse will grow. Poor nutrition though will impact growth in the early years from which your horse may never recover. Horses will usually have finished growing by the time they are 6 years old, but may appear to grow after that as they mature; filling out and muscling up with correct exercise.
