When it comes to caring for indoor plants, most of us turn on the tap without a second thought. But the truth is, the water from your faucet isn’t always what your plants crave. Collecting rainwater — even in small amounts — can be one of the simplest and most sustainable ways to help your houseplants thrive.
Why Rainwater Works Better
Rainwater is naturally soft, free of the salts and chemicals (like chlorine and fluoride) often found in tap water. It’s slightly acidic, which matches the preference of most houseplants, and it carries trace nutrients like nitrogen that encourage leafy growth. Think of it as a nutrient-rich, plant-friendly drink straight from nature.
Benefits of Collecting Rainwater for Indoor Plants
- Healthier Growth: Less chemical buildup in the soil means stronger roots and greener leaves.
- Eco-Friendly: Reduce water waste and reuse what nature provides.
- Budget-Friendly: Every drop you save is water you don’t have to pay for.
- Stress-Free Plants: Sensitive varieties like ferns and calatheas thrive on rainwater’s gentle composition.
How to Collect Rainwater (Even in the City)
- Set out a clean container during a rainstorm.
- Use a rain barrel if you have outdoor space.
- Save snowmelt in winter as an alternative.
- Store properly in a sealed container, away from sunlight, to prevent algae.
Your plants don’t need gallons to notice the difference. Even supplementing once a week with rainwater can give your indoor garden a visible boost.
🌱 Q&A with a Grow Pro: Rainwater & Your Indoor Plants
Q: Can I put rainwater in a mister to mist my plants?
A: Absolutely. Rainwater is ideal for misting since it doesn’t have the salts and chemicals found in tap water that can leave residue on leaves. Misting with rainwater gently hydrates humidity-loving plants like ferns, calatheas, and palms.
Q: How long will rainwater last in my bowl or container before I use it?
A: Fresh is always best. If you’re storing rainwater, keep it in a clean, sealed container and use it within 5–7 days. After that, it may start to develop algae or bacteria. Storing in a cool, dark place extends freshness.
Q: Will rainwater work on succulents?
A: Yes, but sparingly. Succulents need less frequent watering overall, and the softness of rainwater is great for them because it won’t cause mineral buildup in their soil. Just be sure not to overwater — let the soil dry completely between rainwater drinks.
Grow Pro Tip: If you can’t collect rainwater often, let tap water sit overnight in an open container before using. This allows some chemicals to dissipate, making it gentler on your plants.