Aquarium plants are true plants that are able to complete their life span while being in water, on surface of water or on hydric soil. Most of the aquatic plants are perennial and tropical in nature. This simply means that they don’t die immediately but keep on growing.
Aquatic plants grow in either salt, brackish or fresh water but are mostly common in fresh water. Their habitat includes flowing water, standing water and the wetlands that are generally categorized as lacustrine, riverrine as well as palustrine.
Talking about the lifespan
Do bushes and trees live forever? No, right? So, same is the case with aquatic plants. Water sprite is a popular aquatic which is annual in the wild and dies within a year or so in aquariums. However this plant produces a lot of baby plants. Plants greatly vary when it comes to their natural lifespan.
Annuals are the plants that complete their life cycle in 1 growing season and then they die. They first grow, then flower, then set the seed and die. On the other hand, biennials live for a longer span, growing in one season, flowering in the next warm season and being dormant in dry or winter season and become set before they die. Within land plants, Parsley is an example of a biennial.
Then comes the perennials that are way different. They grow, then flower, then set the seed and later they carry right on doing same thing again in the next season, generally after some time of dormancy either in dry or cold conditions.
Aquatic plants in their native habitat may be any of these three mentioned above but we grow them submersed at all times. This means that they may not get a chance to flower.
And when they don’t flower, they cannot even set the seed and when they cannot set the seed, the reaction is hormonal that cause the biennials and annuals to never die. Also, if you take the cuttings, the plant can be immortal as each cutting turns out to be a new plant, just as the original.
Even the lifespan of aquarium plants depend largely on the species of the plant. Some plants have finite life span and they age just like humans. But this is not true of the plants that can grow through fission and do it on their own or by taking help of the cuttings. This then compromises most plants that you can buy.
Irrespective of whether they have a finite life span or not, there are some aquarium plants that require proper lighting and good water quality. Java moss is a very good example of this and given the fact that it gets lighting and gets established and provided with proper nutrients, it will be alive for as long as the system runs and provided that you don’t remove it.
So, it can be derived that there are some plants that live for long say maybe 5 to 20 years, there are others that die just after 1 year.