How to Water Marigolds

Plant marigolds in well-drained soil that contains organic matter. Add compost to the bed prior to planting to improve poor soils and increase the bed's moisture retention properties. Good soil helps provide marigolds with the proper amount of moisture.

Water newly planted marigolds when the top 1/2 inch of soil feels dry, providing enough to keep the top 6 inches of soil evenly moistened. Marigolds require frequent watering the first one to two weeks after planting to establish and produce a healthy root system.

Irrigate established marigolds once weekly when the top inch of soil dries. The plants need approximately 1 inch of water a week, from either irrigation or rainfall.

Apply the water at the base of the plants with a watering can, hose or drip irrigation system. Overhead watering doesn't supply moisture directly to the soil where the marigolds can access it and wet marigold foliage is more prone to fungal problems.

Mulch over the marigold bed with a 2-inch layer of bark nuggets or similar mulch. The mulch keeps moisture in the soil by preventing rapid evaporation during the hottest parts of the day.