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2021 Perennial Plant of the Year

The Perennial Plant of the Year® (PPOY) program began in 1990 to showcase a perennial that is a standout among its competitors. Perennials chosen are suitable for a wide range of growing climates, require low maintenance, have multiple-season interest, and are relatively pest/disease-free. If you are looking for an excellent perennial for your next landscape project or something reliable for your gardens, make sure to check out the Perennial Plant of the Year® archive list.

Since the Perennial Plant of the Year® was introduced in 1990, the Perennial Plant Association has received frequent inquiries about how the Perennial Plant of the Year® is selected. The selection process is quite simple – PPA members vote for the Perennial Plant of the Year® each summer. At that time, in addition to the vote, each member may also nominate up to two plants for future consideration. The Perennial Plant of the Year® committee reviews the nominated perennials (more than 400 different perennials are often nominated each year) and selects 3 or 4 perennials to be placed on the ballot.

Nominations generally need to satisfy the following criteria: 

  • Suitability for a wide range of climatic conditions  
  • Low-maintenance requirements  
  • Relative pest- and disease-resistance  
  • Ready availability in the year of promotion  
  • Multiple seasons of ornamental interest

Like a cloud of confetti, tiny white flowers (sometimes touched with pale blue) appear from early summer to fall. Undemanding and dependable, calamint provides the perfect foil for other summer bloomers and foliage. This full-sun perennial has a low mounding or bushy habit, ideal for the front of the border, rock gardens, and more.

While durable and pest-free, calamint also checks two important boxes for gardeners: bees and other pollinators work the flowers throughout the summer and the aromatic foliage is deer-resistant.

Calamintha nepeta subsp. nepeta is a favorite low-growing component in stylized meadows, matrix plantings, and other modern perennial designs. Gardeners can also create a lovely monochromatic garden with more sure-thing perennials including past PPOYs such as Anemone xhybrida ‘Honorine Jobert’ and Phlox paniculata ‘David’, or complemented with ornamental grasses such as Panicum virgatum ‘Northwind’ (switchgrass) or Schyzacharium scoparium (little bluestem).

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Hardiness: USDA Zones 5 to 7

Light: Full sun 

Size: Up to 18 inches tall and wide 

Native Range: Great Britain to Southern Europe (Griffiths, M. 1994. Index of Garden Plants, Timber Press: Portland, OR) 

Soil: Best with good drainage – tolerates some drought once established. 

Maintenance: Low-maintenance deciduous perennial.  Can shear back lightly if desired to create neater habit or refresh spent blooming stems.  Tolerates drought once established. 

Nomenclature: What’s with the “subspecies”?  Abbreviated subsp. or spp., this is a naturally-occuring, phenotypic variation to a species that is usually related to a geographic situation.  This subspecies was selected for size and vigor.  May also be found under the following synonyms: Calamintha nepatoides and Clinopodium nepeta. 

Grower Notes: Calamintha nepeta subps. nepeta has no patents or other restrictions.  Propagate by vegetative cuttings (stem or root).  Vernalization not required.  Spring planting yields a one-gallon in 8-10 weeks.  Grow on the dry side.  Smaller pot sizes not recommended.  Pinch or shear if needed to shape; responds to plant growth regulators.

Despite its many positive garden traits, lesser calamint (Calamintha nepeta ssp. nepeta) is not suitable or recommended for every region. The Perennial Plant Association cautions against growing lesser calamint, particularly in unmanaged landscapes, in parts of the South and mid-Atlantic where it has escaped cultivation. Shearing plants after flowering greatly reduces self-sowing, which can be prolific and problematic where growing conditions are favorable.

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