You should regularly trim the monte carlo down to 1 cm height regularly... i usually do regular trimming on my plants when they hit around 2-3cm height (while the bottoms are still healthy and green), otherwise if they grow too tall the bottom layers start to brown and can't be saved, then i have to pull out the rotting bottoms and replant the the healthy tops, becomes a huge hassle.
Here is a video that shows the process (pretty much the same as trimming most other carpet plants):
Source: Antonio Nunes
Yeah, these type of carpet plants look nice but need constant maintenance and can be quite messy during trimming work.
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