Perennial dead center question

[tiger15]

Most aquatic plants are bog perennials, yet I've never heard that aquatic plants ever develop dead center, even grown semi emerged in ponds.

Garden perennials are different and many will develop dead center after a few years. A common practice for gardeners is to dig out the dead center to rejuvenate. I am wondering, in nature, there are no gardeners to take up the task so the expanding center would eventually crowd itself to death, right? If it is true, then it doesn't make sense as the plant is committing natural suicide. I recall observing naturalized perennial beds in the wild that show no dead centers as opposed to common occurrence in cultivated gardens. Why?

 

[ElleDee]

Dead centers are, like you notes, associated with overcrowding. This is much easier to achieve in our gardens where the plants are pampered and are spared many of the growth suppressing factors they might have to contend with in the wild (drought, herbivory, poor soil, competition from other plants, etc.). It probably does occur in nature, just less frequently.

Dying centers are actually a solution to overcrowding, not a problem. We don't like to look at them as gardeners, but on an evolutionary scale dying plants return nutrients to the soil and free up space for others.

As a side note "natural suicide" is very, very normal for the plant world! It shortens the life of the individual plant, but it can still give a survival advantage at the species level. Annuals are not made to live more than a year and some perennial plants are monocarpic and die after making seed just once. I think most Ludwigia are monocarpic.

 

[tam]

Irises are one that benefit from splitting and repotting - the most active growing tips are using working their way outwards. Grasses/reeds often benefit from splitting too.

Perenial is basically anything that lives for more than a year though which is a very wide group and they grow in different ways - some only have one stem or grow on runners, rather than naturally form clumps. Being confined to a pot can exacerbate the issue or create one that wouldn't usually exist.

The speed they grow is a factor too - it can take years for a clump to need splitting and a lot of tanks don't run that long.

 

[tiger15]

It makes sense that some plants and animal commit natural suicide as individual for the survival of the species. Cephalopods and annual are classic example. Technically, developing dead center is not suicide, just partial death, as the plant appears to move out in ring. Eventually, the dead center will disintegrate and be reclaimed, but not necessarily by the parent plant. But what caused some perennial to develop dead center, others never. Is it due to over crowding and subsequent exhaustion of soil nutrients. If so, is it possible to accelerate an old perennial to reclaim the center by injecting nutrents at the center, sort like accelerating a tree stumb to disintegrate.

I have a large unfertilized Morning Glory ornamental grass that finally developed dead center after 20 years, yet my heavily fertilized lawn grass never need dividing. Go figure.

 

[tam]

I have a large unfertilized Morning Glory ornamental grass that finally developed dead center after 20 years, yet my heavily fertilized lawn grass never need dividing. Go figure.

Grasses can be clump forming or runners depending on the species. You'd need to identify the ones in your lawn to know which they are.

 

[tiger15]

Grasses can be clump forming or runners depending on the species. You'd need to identify the ones in your lawn to know which they are.

It won’t be desirable lawn grass if the species requires periodic division to eliminate dead centers regardless of growing habit. I have mixture of tall and red fescue in my lawn, the former being clump forming and the latter runner spreading. I had blue fescue ornamental grass in my perennial bed, despite also a fescue species, demands frequent division.