FlytrapCare Carnivorous Plant Forums

I'm mixing a batch of soil for a terrarium that will house VFTs; the terrarium is about 24" long and 12" wide. I plan on putting six inches of soil in the terrarium to give plenty of room for root systems. At six inches deep, that will be 24x12x6=1,728 cubic inches of soil, and this includes the water mixed into the batch.

The soil is about 1:1 sphagnum peat moss to washed sand, maybe a little bit more peat than sand. I put about three gallons of distilled water into this mix. The soil is moist, clumpy, and easily handled, and has no visible standing water.

My question is this: Do I have approximately the right ratio of water to soil for a VFT? All of the instructions I've seen use vague terms, and since this is my first attempt at growing a VFT, I don't have a good idea how moist is too moist and how moist is not moist enough. I'd feel better having some kind of objective metric (one gallon of water per such-and-such volume of soil), if anyone has any to give. Thanks in advance.

I am sorry that I don't know the answer to this, but the advice given to me on these forums has been to not put flytraps in terrariums in general because of the high humidity. Maybe it would work if you kept the lid off to keep humidity down and allow fresh air in?

I am sure one of the more experienced growers will chime in!

Good luck though! I notice you're in Redmond? I am from Edmonds! Good to see another Washington grower!

I see this is your first post: so welcome to our community!

As Slowbomb pointed out, growing venus fly traps in terrariums is usually frowned upon around the forums; it can be done but the humidity and excess water generated through condensation can cause a variety of plant-health issues with mould, fungus, root rot, rhizome rot and from personal experience, bugs.

As long as the air flow is good, you may get away with it (just keep a close eye on your plants' health) and as for water to soil ratios, I wish I could help; I usually just check the surface of the soil and once it looks fairly dry, I water until poking it leaves soil on my finger (heh, not helpful I know).

It may be difficult to give an exact ratio though for many reasons; your plant's health, location, current photoperiod, the fact they are in a terrarium all may impact the amount of water you need per watering. I really hope someone else can give you more advice than me, and I'm sorry I couldn't help more.

Hello and welcome to flytrapcare! Grey has already given you all sort of helpful information. If you have any follow up questions, feel free to ask

It is kind of vague terms: "moist, but not wet," but you can't really give an accurate ratio because the ratio of water to soil is always changing in a pot, and after the plant is potted you can't really measure that anyway. Some people say that you should let the soil dry out until the top just starts changing to a lighter color, then water. This is a little dryer than I like to keep plants, as it'd probably be easy to over-dry your plant that way. Other people say, if you stick your finger on the top of the soil, it should come away with a little bit of soil attached, and that's the measure of correct wetness. Too wet or too dry and I think this doesn't happen. It also depends on how big your pot is, because the soil on the bottom will always be wetter than the soil on the top and serve as a sort of reservoir. If you have a soil mix with good drainage, you can keep the soil wetter and not worry as much. You haven't read a straightforward answer because the answer isn't straightforward. And it doesn't need to be perfect. If the plant's not happy it'll tell you. You might just want to pick a method, and post a picture of the plant in six weeks or so, and people will be able to give you good advice on if it's happy.

In addition to other problems mentioned with respect to a terrarium, if one hopes to use real sunlight instead of artificial lighting, it can literally bake and kill the roots and plants when direct sunlight enters the transparent sides of the terrarium into the growing medium and root zone, and the air surrounding the plants, which can heat up startlingly fast to lethal temperatures.

So be careful, and have fun. Better yet, forget about a terrarium and grow the plants in pots and fresh air. Low humidity won't hurt Venus Flytraps at all.