How to Plant Dutch Iris Bulbs

Hardiness and planting time:

Dutch iris (Iris hollandica) are hardy perennials that can tolerate
temperatures down to around -15°C, making them suitable for planting directly
outdoors in most regions. The best time to plant Dutch iris bulbs is from
September through December, either in garden borders or in patio containers.

Soil and location:

These bulbs prefer free-draining soil but will also tolerate heavier soils that
have some clay content, provided drainage is improved. For container planting,
use a soil-based compost or a multipurpose mix with added loam. Choose a sunny
position for the strongest flowers, though Dutch irises will also grow well in
light partial shade.

How to plant Dutch iris bulbs:

Plant bulbs with the pointed end facing upwards, setting them about 10–15 cm
deep in borders or containers. Space bulbs 5–10 cm apart to allow enough room
for growth while still creating a striking display.

Watering and care:

After planting, water the bulbs well to help them establish. During their first
year, keep the soil lightly moist while they are in active growth. Once
established, Dutch irises typically need little additional water unless the
weather is very dry.

After flowering:

When the blooms fade, cut back the flower stems but leave the foliage in place
until it naturally dies back, as this allows the bulb to store energy for the
following year. In autumn, trim back the foliage to ground level. Dutch iris
bulbs are fully hardy and can be left in the ground year-round without the need
for frost protection.