Perennials are plants that live at least 2 to 3 years. Shallow-rooted perennials are low-maintenance plants with multiple roots growing near the soil surface. There are many shallow-rooted perennials.
Shallow-rooted perennials include the purple loosestrife (Lythrum salicaria), yarrow (Achillea millefolium) and Egyptian onions (Allium proliferu L.). The purple loosestrife is indigenous to Europe with approximately 50 stems. Yarrow takes 2 years to mature and is native to Europe. Egyptian onions are fall season perennials that originated in the Northern Hemisphere.
Perennials with shallow roots require 1 inch of water per week. When rainfall is sparse, using a soaker hose enables the plant to receive the proper amount of moisture. Shallow-rooted perennials need light mulching, as heavy mulching causes these types of plants to smother and die.
Shallow-rooted perennials planted over septic tanks or drain fields help disguise the placement of unsightly equipment. Gardeners use shallow-rooted perennials for groundcover. Some shallow-rooted perennials, such as onions, are edible and grown as agricultural crops.