We recommend not using use any Beta fish plant except the natural water plants that are not toxic to beta fish.
If you notice that the plants' roots are growing too large or are becoming brown and soggy, you should cut them back.
If the plant becomes too large at the top you should separate the plant from that part of the plant that is not being used. Chinese evergreen is considered to be one of the best water plants, mainly for their ability to tolerate very low lighting.
You should not get plants for use in a vase. In a vase the plant is merely for looks, and is not contributing anything of real value to the fish. It will be much easier to care for your Beta fish in a vase if don't have any plant in the way.
The best environment for any fish is one that closely matches its natural home.
It is not impossible make a reasonable home for your Beta fish if you are willing to make the effort. In warm climates a beta fish can do pretty well in a tank or vase, provided the owner changes the water regularly, keeps the tank or vase clean, and provides the proper diet.
See our entire selection of beta fish plants