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Watering

The use of rain water is essential if a Venus Fly Trap is to flourish.  Tap water can be used in an emergency, however the chemicals and salts generally found in the mains supply, will tend to build up in the compost, and kill the plant if used for any length of time.  Boiling of tap water actually concentrates the nitrates in the water and so is not recommended. 

Pond water is usually an acceptable substitute for rain water.  If it is intended to use this source as the main supply it may be advisable to have the water tested to determine its chemical composition. 

Certainly do not use if the water is alkaline or has any traces of nitrates.  A water butt or barrel is the best way of collecting rain water, these can easily be connected into a fall pipe using connections readily obtainable from most local DIY shops or warehouses. 

During the growing months the pots should be stood in 1 - 2 cm of water, care should always be taken to ensure the compost is never allowed to dry out.  Towards the end of the growing season as the temperature starts to drop the level of water should be gradually reduced, until the plant is watered as and when required.  Throughout the winter months the compost should be kept just moist. 

As new growth appears in the spring, if the pot is stood in a tray, the plants should be allowed to just stand in water, this should be replenished when the tray is completely dry.  As an indication the plant should require water about once a week, more than this and there is a risk of the compost drying out, less than this would indicate too much water is being supplied.  This rule can generally be used throughout the summer, the only exception being during extremely hot and dry conditions.