Before we begin I should mention the scientific name for a Venus Fly-Trap is Dionaea muscipula. You will come across this name if you pursue learning more about this plant. Venus Fly-Trap’s and Dionaea muscipula are one and the same.
1. Let there be light, aplenty
Venus Fly-Traps need full sun. Actually it’s fair to say the amount of shade you give them is directly proportional to their likelihood of death. They are not going to survive on your windowsill, kitchen table or under your veranda. They want to see the sun. If you want happy, healthy and colourful plants you had better let them. Besides, outside is where the flying, buzzing, crawling and biting food is.
In the hotter months, where temperatures are in the high 30’s or low 40’s it is a good idea to provide some shaded protection from the scorching afternoon sun.
Now the good news is, lack of light won’t kill a Venus Fly-Trap immediately. There will be warning signs. Long leggy and weak growth, pale and chlorotic colours, mould and fungus on the plant or on the soil are all common indicators light levels are too low. In severe cases the plant may start to rot from the inside out. Look out for these signs to prevent a disaster.
2. water, water and more water
Venus Fly-Traps need a lot of water. They like conditions akin to bogs. A Venus Fly-Trap who is sitting in a few centimetres of water between spring and autumn is going to be right at home. A daily watering from the top will be warmly received too. Just be aware of the distinction between bog plant and aquatic plant – Venus Fly-Traps can’t swim, or hold their breath.
You may have experience growing other plants, for example African violets, where over watering can cause imminent death. Venus Fly-Traps have the opposite problem, many growers kill their plants from under watering. They won’t give you a second chance.
The type of water you give really matters. You must only water your plants with rain water or preferably demineralised water. There’s a long and complicated reason for this and if you are interested it is available here. The short reason is Venus Fly-Traps have adapted to environments very low in nutrients. Tap water adds nutrients to your soil, and in time (depending on which and how many dissolved solids are in your water) will kill your plant.
You may think your water is OK, that you will get away with watering with tap water. Maybe you even think we have shares in a water distillery! Let me tell you, it isn’t, you won’t and we don’t. Rain water or demineralised water only.
3. Soil, hold the nutrients
Every couple of years you will need to divide and repot your Venus Fly-Trap into another plastic pot. You must only ever pot your Venus Fly-Trap up in acidic, low nutrient growing media. There are a few proven and accepted blends. 50% sphagnum peat moss and 50% sharp propagating sand works well. This blend can make the pot heavy, so using perlite instead of propagating sand works too. Other growers use 100% long fibre sphagnum. While some use 1/3 sphagnum moss, 1/3 sphagnum peat moss and 1/3 propagating sand. There’s more information about repotting and media preparation here.
Never stray from the core growing media ingredients. I don’t care how well your tomatoes grow in your home made, manure fortified premium potting mix. It will kill your Venus Fly-Trap. Don’t try to save money and use cheaper substitutes – coconut fibre is not a suitable replacement for sphagnum peat moss. River or beach sand is not a replacement for sharp propagating sand. Also ensure none of your ingredients contain any added fertiliser. This is a trap especially with sphagnum peat moss. Some suppliers add pH neutralizers and fertilisers to their peat. Venus Fly-Traps can’t handle soil conditioners or fertilisers. They will never forgive you until the day they die. You make take some solace in the fact it will be a short grudge.
All parts of your growing media should be independently washed with rain water or demineralised water to remove any excessive nutrient or salt content. The best way to do this is to use a sieve to clean the raw ingredients and allow the water to drain away. Repeat the process at least four or five times with each ingredient. Once you’ve replanted your Venus Fly-Trap give the plant a slow but steady water from the top until at least three times the volume of the pot has been flushed through. Allow the excess water to freely drain away. Don’t collect it or allow your plant to sit in it.
If you have a TDS (Total Dissolved Solids) meter you can check the water coming out the bottom of your pot by collecting it in a clean container. The TDS should be < 50ppm (parts per million). The lower the TDS the better. TDS meters can be picked up at most hydroponic stores for between $30 – $50.
4. Sleep, better than caffeine
Venus Fly-Traps need to go dormant during winter. Dormant plants will die back and sink into their pots. Traps will be much smaller if they are present at all. Dormancy is not only normal, but also necessary for survival. Dormant Venus Fly-Traps look a miserable shell of their former self. Often inexperienced growers throw their plant away thinking it has died. Don’t make this mistake.
Dormancy allows the plant to rest, divide and protect itself from the winter weather. Venus Fly-Traps need less water during dormancy. Don’t let your plant sit in water during winter. Frosts and occasional brief freezes won’t damage a Venus Fly-Trap. Even during dormancy though, the plant still needs as much light as possible.
You might be thinking of cheating by keeping your Venus Fly-Trap artificially warm and under light? Don’t do it. It will likely work, and you will end up with a weak plant that eventually dies from utter exhaustion. There’s no coming back from that. Always respect a plants life-cycle.