As this lobelia grows so easily from cuttings we, in the Harold Porter National Botanical Garden do not bother to attempt to grow it from seed which is very small and not easily gathered. Cuttings can be made almost all year round except for the coldest months and will readily root in a mixture of 50% well rotted finely sieved pine bark and 50% polystyrene granules (by volume) which is kept constantly damp. The cut surfaces of the plant exude a milky sap which must be allowed to dry out for at least ten minutes before dipping into a rooting hormone powder for soft cuttings. The trays of cuttings are sprayed with a fungicide before being placed in the misthouse. Rooting occurs within 2-3 weeks and the cuttings can then be planted directly into position if the area remains damp, or they may be potted up into a mixture of 10 parts of clean river sand, 6 parts of loam soil and 15 parts of organic compost. Plants can be fed with a liquid fertilizer.

Lobelia anceps makes a wonderful display around stepping stones or flagstones, or round ponds or in boggy areas, especially when combined with Monopsis lutea, the yellow lobelia, another damp-loving groundcover, as the combination of blue and yellow flowers is most attractive. Lobelia anceps may even grow out from the soil banks of a still or slow-moving water body to form a mat on the water surface.