Tortoises cannot eat runner beans because they contain too much protein, as well as the lectin phytohaemagglutinin which is toxic. However, you can give them the leaves of the plant as long as you do it in moderation.
Runner beans are known to be quite delicious. The plant has a beautiful green shade, and its blooms also have a wonderful color palette of red hues. It is commonly grown not only for it’s use as a food but also as an ornamental plant. Because the beans can be so delicious for us humans, you might be wondering if your pet tortoise can eat them as well. So, is this plant safe for the reptile? Let’s find out!
What Are Runner Beans?
Runner bean or phaseolus coccineus, also known as multiflora bean or scarlet runner bean, is a plant that is commonly used as a food source for humans. It is part of the legume family Fabaceae. Runner beans have been eaten for many hundreds of years in Britain and the USA, retaining their popularity thanks to their delicious taste.
It should be noted that these beans are different from the common bean. For example, the plant has tuberous roots, and it is a perennial vine while having cotyledons that remain in the ground during germination.
The bean pods the plant produces are shaped just like knives, and they are green in color. In some rare cases, amateur breeders have successfully bred different varieties featuring purple pods.
One of the most appealing things about runner beans is that they can be successfully grown in a range of different climates. They tend to do better in cool spring soil when it comes to germinating. In fact, they do much better compared to traditional green beans, and it is even possible for them to develop over-winter in some places, although this depends largely on whether the ground freezes or not because frozen ground will not allow the plant to germinate.
Can Tortoises Eat Runner Bean?
If you come across runner beans or grow them yourself, you may be wondering whether they are safe for your tortoise. Well, it depends on which part of the plant you decide to feed to the pet. After all, the beans contain several vitamins and minerals that can be very useful. Runner beans can be a source of:
- Vitamin C
- Vitamin K
So, yes, the beans might be healthy… for humans. However, you should never feed the beans themselves to tortoises – and this is true regardless of whether the beans are cooked or not. They can be harmful to your tortoise.
The only part of the plant you can feed your tortoise are the leaves, particularly young leaves. But even with these, you should only offer them in moderation. So, you can only feed the leaves as long as you make sure to combine them with other foods or weeds.
Runner bean leaves also have some protein in them, but not at the level found in the beans themselves. Again, if you do feed them make sure they only form a small part of the diet and that you only give them to your reptile once in a while. This way, they will not pose any health risk.
Why Are Runner Beans Harmful to Tortoises?
While runner beans may seem harmless, they cannot be given to tortoises because they contain toxic compounds. Sure, they may be safe to eat for humans, and I can certainly attest to the fact that they are delicious if you cook them well, but a tortoise will not have the same experience with this plant.
Runner beans contain a lot of protein, which is not good for tortoises. Since they are mainly herbivorous they have developed in such a way that they instinctively eat foods which are low in protein. As a result, they consume plants that contain a lot of fiber and very little protein. This means that too much protein will not be beneficial, and while it may not exactly affect digestion, it can affect the tortoise’s shell. Consuming large amounts of protein will make the shell of a tortoise grow much faster, but also turn less dense in the process. This might activate the pyramiding process in the shell, which is something you want to avoid at all costs.
On top of that, excessive protein can also adversely affect the kidneys. Protein breaks down nitrogenous waste, which is then sent to the kidney. This can cause the organ to overload. If tortoises do not drink enough water after consuming a lot of protein, they can go on to develop kidney stones.
Another issue with eating runner beans is that they contain the lectin phytohaemagglutinin, which is a toxic compound. It can be destroyed at very high temperatures, so it will certainly be denatured if you cook the beans, particularly at temperatures of 212 degrees F for at least 10 minutes. But this doesn’t mean that tortoises should consume cooked beans.
It’s best to stay on the safe side and stick to only offering the leaves, and only in moderation.
The Bottom Line
So, hopefully you’ve now got a pretty good understanding of why runner beans are not safe for tortoises, certainly not the actual beans at least. Not only do they contain a lot of protein, but they also contain phytohaemagglutinin, a known toxin that the reptile should not ingest.
In order to avoid kidney stones, shell scute pyramiding, and other health issues, tortoises should not be offered runner beans. The only parts of the plant they can eat in moderation are the leaves. These can be safely combined with the other foods your tortoise eats. Just do not make it a habit from feeding runner bean leaves, especially not in combination with other relatively protein rich plants such as clover, or even tortoise pellets.
So, keep things safe – make sure the runner beans only stay on your plate and do not make it to your tortoise’s enclosure!