Slow Growth Rate

[Born]

Greetings PalmTalk,

This is my first post. My passions are that I fly airplanes and grow palms. 

I have attached pictures of my two Trachycarpus Fortnei, one Phoenix Robellinii, and one Washingtonia Robusta. I have also attached my 2500 sq ft whole room humidifier that I use. Once a month, each tree is brought into the shower and, with warm water, I rinse each leaf and water the soil until there is drainage. 

As I live 2 hours south of Chicago, all trees are grown on the south facing windows in my condo. 
 

I am inquiring on how to slow the growth rate of the Washingtonia Robusta. Do I continue to use the small planter to prohibit growth height rate?
 

Any guidance or suggestions would be very much appreciated. 

 

[Palmlover_78]

Hello, The first photo with your Washingtonia Robusta looks a bit too big for the size of the tree, I wouldn't transplant in for at least 5 years, The true way to slow there growth is not to match there environment. lower light, cooler temps, depending on what the Plant likes, I have a Trachy and it was taking off like a rocket, but the humidity in my apartment now  is 45% and about 18 C. in lower light, it has slowed down quite a bit. hope this helps somewhat...I want to fly planes and I love Plants

[Born]

Thank you for the response. 

The first photo is a Trachycarpus Fortnei. 

The third photo is the large Washingtonia Robusta (in the shower). I purchased a very small planter yesterday and placed the Washy in it. I suppose I will just keep the root ball from growing and expanding which should prohibit expedited growth. I am providing 50% humidity, fertilizer, porous soil, and south-facing light from a window. 
 

Again, thank you for your response.

 

Edited April 24, 2021 by Born