With almost 800 species from 7 different plant lineages, carnivorous plants are as diverse as the prey they seek to consume. You might think that because they are such specialists, they might be difficult to grow. But for many species, if you follow just a few simple rules, they’ll not only grow, but they’ll thrive!
Greg Bourke, Curator Manager at The Blue Mountains Botanic Garden in Mount Tomah, Australia, tells us about five things that carniverous plants love:
Carnivorous plants love light! Well, most of them do. You can grow your plants outside in full sun, inside on a bright windowsill, or in a terrarium under lights. Like most plants, your carnivorous plants will tell you if they’re not getting enough light by becoming leggy and/or losing their colour
Water, Water, Water! There are three very important water related rules you need to follow. As most carnivorous plants come from swamps or bogs, they love water. Plants like the Venus’ Flytrap (Dionaea muscipula), North American Pitcher Plants (Sarracenia spp.), Sundews (Drosera spp.), Butterworts (Pinguicula spp.), and Bladderworts (Utricularia spp.) should sit in shallow water trays year round and never be allowed to dry out.
Humidity is important. Most will tolerate low humidity for some time but avoid growing your plants near air conditioners. Bathrooms and kitchens are perfect places for indoor growing as these tend to be more humid than other areas of the house. You can of course grow your plants in a terrarium to ensure humidity is kept high.
Water quality. In some areas, tap water is not suitable, so if your tap water is soft (ph above 6.5) or high in dissolved minerals, you may need to use rain or bottled water.
3. Potting mix
Most carnivorous plants live in acidic, nutrient-poor soils, so in cultivation, they will struggle or even die if planted in standard potting mix. Instead, a mix of peat and washed river sand is preferred. Of course, there are some great sustainable peat substitutes that can be used such as those derived from pine bark or coir.
All plants need food! Like most plants, carnivorous plants photosynthesise so they can survive without feeding, but they will thrive if fed. With the Venus Flytrap, live insects are best, and they don’t need many to do well; just a few each year is enough to sustain them. The sticky plants can be fed fish food flakes, live or dead insects or diluted liquid fertiliser such as those used for orchids. If your plants are outdoors though, they’re likely to lure and kill their own food!
One of the biggest mistakes people make with their precious Flytrap is throwing it away in winter thinking it’s died. The leaves can turn black and die rather dramatically as temperatures drop in Autumn. The plant looks dead but under the surface, the plant survives as a corm, awaiting warmer days when it will burst back into growth. The same goes for some of the sticky plants and the taller growing Sarracenia. Cut off dead leaves in late winter and you’ll be rewarded with new growth, and often flowers come Spring.
Follow Greg on Instagram here, and visit The Blue Mountains Botanic Garden wesbite at bluemountainsbotanicgarden.com.au