Like i said, in my experience swords can be slow growers in low techs when young. They will grow given time. The important thing is they are healthy. Once they do get going they can go like crazy and get very big quick.
I have a couple of Ozelots.
Ozelot red and Ozelot green. Beautiful plants and fast growers.
Ild recommend the red species
Good choice of plant. I prefer these over swords.