Watering a Garden With Softened Water

You can water your garden with softened water.

Soft water is water treated with softeners to remove minerals, such as calcium and magnesium. Soft water makes excellent water to use for washing dishes, doing laundry and taking baths. However, it is not ideal for watering your lawn and garden. Soft water is high in sodium and leaves sodium deposits in the soil. These deposits hinder the uptake of water by plant roots and can stall growth. If you have no choice but to use soft water for your garden, a few techniques can help reduce the problems that arise.

Difficulty:

Moderate

Instructions

Things You'll Need

• Gypsum

1. Water with soft water when rain is in the forecast, if possible. The rainwater will send the soft water you used deeper into the soil and away from your plants' roots, thereby minimizing sodium deposits.

2. Water heavily -- about 2 to 3 inches of water -- when rain is not in the forecast. This will wash away some of the sodium buildup from previous waterings.

3. Apply about 5 lbs. of agricultural grade gypsum for every 100 square feet of garden space. Broadcast evenly with your hands or use a broadcast spreader. Carefully work the gypsum into the top 3 inches of soil with a hoe or garden rake, and then water your garden with approximately 4 inches of water.

4. Choose salt-tolerant plants for your garden, such as those that grow in coastal areas.

Tips & Warnings

• Apply gypsum two times a year -- in the spring and early fall. Gypsum is calcium sulfate and dissolves over time. It displaces the sodium buildup and helps counteract the effects of soft water.

References

• Water Quality Association: Water Quality Answers
• LoHud: Ask the Master Gardeners: Soft Water on Plants
• Arizona Cooperative Extension: Water for Irrigation
• University of Arizona: Fertilizing Home Gardens in Arizona

Resources

• Rittenhouse: Salt Tolerant Plants