Siberian Iris

In late June, delicate flowers dance above tall slender slate-green foliage that looks good all summer. Tolerates most conditions, but performs best in rich moist acid soil.

Plant 18" apart in full sun or partial shade. Give them room to spread, and divide clumps every few years.

Achillea

Blooms June through September featuring 2–3" flat-topped flowerheads. Ferny green foliage is aromatic when crushed. Excellent filler for fresh and dried arrangements. Prompt removal of faded flowerheads guarantees a long season of blooms. Colors can fade out in extreme humidity but regular cutting will keep the blooms looking bright and fresh. It’s a sweet and easy early morning task to walk the yarrow path and cut quick bouquets. Plant 12–24" apart in well-drained soil, full sun to part shade. (See also: white yarrow Achillea millefolium)

Herbaceous Perennial Plants

When you receive your order, open the bags and check the stock immediately. Roots and crowns should be firm and pliable. Surface mold is harmless and will not affect the plant’s future performance. Store plants in their packaging in a cool (35–40°) location until you are ready to plant. If it’s going to be awhile, you can pot up your perennials.

Do not plant bare-root perennial plant crowns directly outdoors before danger of frost has passed. Wet and/or cold conditions for an extended period may cause rotting.

For more info:
About planting bare-root perennials