How to Water Carnivorous Plants – Complete Guide


I have grown carnivorous plants for several years and know watering them correctly is extremely critical to keep them alive. In this article, you will learn all you need to water your plant and keep it healthy.

Water carnivorous plants with pure, mineral-free water, such as distilled, reverse osmosis, or rainwater only. Carnivorous plants thrive in moist and waterlogged conditions. Some varieties require more water than others, but all carnivorous plants require humid environments.

The minerals present in most tap water and standard bottled water harm carnivorous plants and can kill them. In this article, you will learn how to select appropriate water and how much water your plant needs. For example, Sarracenia plants require a lot more water than Venus flytraps, so make sure you don’t treat all carnivorous plants the same in terms of watering frequency.

What Type of Water Should You Use for Carnivorous Plants

The water type you select is extremely critical. Carnivorous plants should only be watered with the following pure water sources:

  • Distilled water
  • Reverse osmosis water
  • Rainwater

The table below has a comprehensive list of water types and how suitable are they for carnivorous plants:

Water TypeSuitable for Carnivorous Plants
Distilled waterYes
Reverse osmosis waterYes
Rainwater Yes
Tap water Sometimes (depending on the composition)
Bottled waterNo
Boiled waterNo
Purified waterNo
Filtered waterNo (except when using the ZeroWater filter properly)
Spring waterNo
Safe Water For Carnivorous Plants

Some tap water and bottled water is not suitable for carnivorous plants. However, depending on the brand and where you live, the mineral content could be low enough for your plants. Unfortunately, the labels won’t give you much information. You would need to measure the Parts per Million (PPM) with a TDS meter to determine the mineral content in the water.

A TDS meter is a very simple tool you can buy on Amazon for less than $15 https://amzn.to/3g8VKLI. By dipping one of the ends of the tool into the water, you can measure its parts per million or PPM. Optimally you should employ water with 0 PPM. However, most carnivorous plants can handle some mineral levels.

What is the maximum amount of minerals your carnivorous plants can handle?

Sundews and Venus flytraps are the most sensitive carnivorous plants, while Nepenthes and Sarracenia can handle some minerals in the water and soil.

Maximum recommended PPM level:

Carnivorous PlantRecommended PPM Level
Venus Flytrap< 50 PPM
Sundew (Drosera)< 50 PPM
Nepenthes< 100 PPM
Sarracenia<120 PPM

Where I live the PPM in tap water exceeds 500 PPM, using my tap water will harm and kill carnivorous plants very quickly.

How to Get Water for Carnivorous Plants

I personally buy distilled water for my carnivorous plants, but you can decide what works best for you between distilled water, reverse osmosis water, or rainwater.

Distilled Water

Where to purchase: grocery store, pharmacy, water store

How to make: You can follow this easy method to make distilled water at home.

How to select: Most grocery chains and pharmacies will sell plain distilled water. I usually buy the 1-gallon jugs labeled as distilled water in Walmart or Kroger. When selecting a jug of distilled water, read the label. The distilled water must be completely pure. If the bottle says something like “enriched” or “added mineral for flavor” then it is not pure and can kill your carnivorous plants.

Reverse Osmosis Water

Where to purchase: Water stores and some pharmacies

How to make: You need a reverse osmosis system to make RO water

How to select: make sure to ask for pure reverse osmosis water. It is helpful to ask if it has additives or minerals for taste. The answer to all those questions should be “No”. Bottled water is commonly purified through reverse osmosis, but then minerals are added.

Rainwater

Rainwater is the only free option available if you have access to enough rain throughout the year. If you collect rain, make sure you do not store it in clay or metal containers. those materials can leach minerals to the ground.

How to Water Carnivorous Plants

This table summarizes the main considerations for watering the most common carnivorous plants. For more detailed explanations for watering Venus flytraps, Nepenthes, Sarracenia, and Sundews, read the sections below.

Watering FrequencyWater Tray MethodMineral SensitivityMaximum Recommended PPM
Venus fly trapKeep the soil humid at all timesRecommendedHigh50 PPM
Pitcher Plant (Nepenthes)The soil must be humid, but the plant should never sit in waterNot RecommendedMedium100 PPM
Sundew (Drosera)Keep the soil wet at all times Recommended High50 PPM
SarraceniaKeep the soil damp at all timesRecommendedMedium120 PPM
Watering Carnivorous Plants

Water Tray Method

Venus Flytrap Humidity

The tray method is a very common technique to water carnivorous plants. Make sure you are using a pot with drainage holes. Then, place the pot on an empty tray. Instead of water by adding water to the soil. Fill up the tray and let the soil soak the water from the tray.

Should carnivorous plants sit in water?

Carnivorous such as Sarracenia and most Sundews thrive continuously sitting on water. Venus flytraps can also sit on water for several days in a row until the tray dries out. Nepenthes on the other hand are prone to root rot and should not sit on water.

Venus Flytrap Watering Instructions

Water Venus flytraps often to keep them healthy. The soil must remain humid at all times; never let the soil dry out completely. You must also avoid soggy or waterlogged conditions as Venus flytraps are prone to rotting due to overwatering.

Some people believe Venus flytraps are aquatic plants, and unfortunately, end up killing them by watering them excessively.

I water my Venus flytraps by using the tray method. To be successful you need to add 1-2 inches of water to the tray. Then, let the plant consume the water. Do not water again until the tray is dry.

If you are unable to use the tray method, you can also water them from the top. Use pure water to moisten the soil all around until is humid. Touch the soil to confirm is wet, but not muddy. Then, let the plant consume the water and do not water again until the soil is slightly drier.

The presence of mold or algae in the soil are common signs of overwatering. Droppy Venus flytraps or excessive amounts of black leaves are sometimes due to underwatering.

Read this complete guide on Venus Flytrap Watering for a complete explanation.

Sundew (Drosera) Watering Instructions

Sundews thrive in waterlogged conditions. They should be watered with pure water and kept in humid to damped soil at all times. For best results, keep Drosera in trays filled with water up to one-half of the height of the plant’s pot.

If you grow Sundews indoors, consider using the tray method, but do not overfill the trays. Keeping the water level in the trays to 1/3 of the height of the pot can prevent overwatering.

Sundews are very difficult to kill by overwatering them; they are a lot more likely to suffer due to underwatering.

For complete instructions to water Sundews through the seasons, read this article I wrote for you 🙂

Nepenthes Watering Instructions

Watering pitcher plants can be tricky. This is due to the high humidity level necessary to grow a healthy pitcher plant, and the fact that the soil needs to stay humid at all times.

Pitcher plants require consistently humid soil at all times. However, the tray method is highly discouraged. Nepenthes are prone to root rot. Leaving Nepenthes sitting in water for long periods can be harmful.

To water Nepenthes, use distilled, rainwater, or RO water and moisten the soil throughout. Then, empty any excess water out of the tray. Test the soil every couple of days by touching it and water when the soil starts to dry out.

Sarracenia Watering Instructions

Sarracenia plants are extremely difficult to overwater. they actually thrive in wet soil year-round.

Employ the water tray method for Sarracenia. Fill up their trays with water until the soil is wet throughout. Then, let the water in the tray consume slightly and refill to the original level.

Sarracenia can live sitting in water without issues.

Nelly

My name is Nelly, and I am the owner of Venus Flytrap World. Growing carnivorous plants is a unique and rewarding experience. A few years ago, I started growing Venus flytraps and experimenting with other carnivorous plant species. I have done tons of research to perfect my setup and care practices. In this site, I share everything I have learned.

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