Lobelia Cardinalis

• Hardiness: Easy
  
• Light Needs: Medium
  
• Plant Structure: Stem
  
• Family: Lobeliaceae
  
• Genus: Lobelia
  
• Region: Cultivar
  
• Location: Cultivar
  
• Size: Stem width: 3-7cm / 1-3 inch
  
• Growth Rate: Medium
  
• Can Be Grown Emersed: Yes
  

Lobelia cardinalis 'Small Form' is an interesting and highly desirable cultivar derived from the much larger, original L. cardinalis. There is much confusion in the United States as to which plant is L. cardinalis 'Small Form' and which are just small or stunted L. cardinalis. They can be differentiated by the much rounder, coin shaped leaves and the much smaller stature of the former compared to the latter. So far, only Oriental Aquariums in Singapore commercially offers the true variety. This plant is now relatively common in the United States and is becoming in Europe.

L. cardinalis 'Small Form' makes few demands on the hobbyist other than ample amounts of direct lighting (2 watts per gallon or more). However, to obtain optimal growth both in size, coloration, and growth rate, CO2 supplementation should be used along with a water column rich in both macro- and micronutrients (NO3 10-20ppm, PO4 1-2ppm).

Under rich water column conditions, CO2 supplementation, and strong lighting, this plant will become bushy and lush, concentrating most of its growth on producing daughter plants which can be snipped off with a pair of scissors and replanted to form a new plant. The internodal roots, under these conditions, will be concealed by numerous side shoots and dense foliage. Under less than optimal conditions and dim lighting, the plant will become leggy and less attractive, producing fewer side shoots and, thus, not as easy to propagate.

The unique appearance and growth habit of this small plant make it an excellent choice for the midground of aquaria ranging from small to large. In large aquariums, this plant can even be used as a low maintenance foreground. It is often used in the Dutch Aquarium style to form diagonal, sweeping streets which add movement to otherwise static plant groupings. Because it is slow to gain vertical height, it is highly suitable for those hobbyists trying to cut down maintenance on their aquascapes.