+1 for either patience or moving to C02.
I run low to moderate light tanks, no C02, sand substrate with root tabs and somewhat regular ferts in the water column and in general I find it takes a couple weeks to a month for a recently moved plant to settle in and start new growth. Java ferns are actually slower growers than anubias for me--healthy, but slow to fill in. My mother plant is mounted on a 3"x6" piece of driftwood and I usually only divide it once a year--taking about 1/3 of the mass off to keep it to a reasonable size.
Some folks find that sort of growth intolerably slow. For them, C02 is probably a good choice. For me, it's an occasionally frustrating but ultimately fulfilling reminder to appreciate a slower pace.