How to Grow Watercress

Growing guide

Overview

Watercress is a fast-growing, peppery green that thrives in cool, wet conditions and partial shade. It’s a beginner-friendly crop that rewards you with repeated harvests of nutrient-dense leaves. The key to success is keeping the soil consistently wet and the weather cool.

Soil & planting prep

Watercress prefers rich, loamy soil that holds moisture but drains just enough to prevent stagnation. Aim for a pH between 6.5 and 7.5. Space plants 6 to 8 inches apart, and sow seeds just 1/4 inch deep.

When to plant

Start watercress outdoors 2 to 4 weeks before your last frost date in spring, or in late summer for a fall crop. It tolerates light frost, so you can plant as soon as the soil can be worked. In hot climates, grow it in partial shade or as a fall-to-winter crop.

How to plant

1. Choose a spot with partial shade and rich, loamy soil that stays consistently moist.
2. Sow seeds 1/4 inch deep, spacing them 6 to 8 inches apart in rows 12 inches apart.
3. Keep the soil constantly wet by watering daily or setting the bed in a shallow tray of water if growing in containers.
4. Thin seedlings to 6 inches apart once they have two sets of true leaves.
5. Mulch lightly to retain moisture and keep the soil cool.

5 common mistakes to avoid

• Letting the soil dry out even once: watercress is an aquatic plant and will bolt or die if the soil dries, so check moisture daily and water generously.
• Planting in full sun during hot weather: watercress prefers partial shade and will turn bitter or bolt in heat, so provide afternoon shade in warm climates.
• Growing in stagnant water: watercress needs fresh, moving water; in containers, refresh the water regularly to prevent mosquito breeding and root rot.
• Harvesting only the inner leaves: watercress regrows from the outer stems, so always pick the outer leaves to encourage new growth.
• Fertilizing with strong chemical fertilizers: watercress is sensitive to burn; use compost or a diluted organic fertilizer instead.

Harvesting & storage

Watercress is ready to harvest 30 to 60 days after planting, when stems are 4 to 6 inches long. Snip or pinch off the outer leaves and stems, leaving the inner crown to regrow. Store harvested leaves in a plastic bag in the refrigerator for up to a week.

Companion planting

Good companions for watercress include mint, which also likes moisture, and radishes, which grow quickly. Avoid planting near tall, invasive plants that may shade it too much or compete for water.

Growing in containers

Watercress grows well in containers at least 3 gallons in size. Keep the container in a saucer of water and refresh it regularly to mimic the plant’s natural running-water habitat.

Pro tips

Grow in a container of rich soil kept standing in water, refreshed regularly. Harvest outer leaves often. Prefers cool shade to hot sun.