Ludwigia glandulosa (''perennis'') not growing

[Cardinal Tetra]

ever since i planted this red plant Ludwigia glandulosa (''perennis'') into my tank 2 weeks ago its growth has remained stagnant. all my other plants are doing well.

tank info.
specs:60x35x30cm
light:2x18W FL 1x36WPL
base fert: JBL
gravel: dennerle
filter: internal
co2: DIY

pls take note that all the other plants are doing very well, only that red plant is not showing any signs of growth.
i have no test kits, and because the tank is still new, i have no readings of any sort.
i know this may not be much help but could someone tell me what increases the growth of red plants?

[www.Aquatic-Store.com]

Do you fertilize the water with anything I notice when i stop fertilizing with flourish it stops growing

www.Aquatic-Store.com

Co2, filter, tanks, plants and more

[PeterGwee]

Basically, you need a complete set of nutrients to enable plants to grow...once they stop growing, algae will...

CO2 : Check your pH and KH to find the amount of CO2... Use the link here to determine CO2 level using pH and KH values

Macros: Nitrate, Phosphate, Potassium, Magnesium, Calcium.
Micros: Traces..TMG, Flourish, Sera, JBL and etc.