2017 Green Leaf Plants Field Trials Results

2017 Green Leaf Plants Field Trials Results

Green Leaf Plants’ trial gardens cover about 1acre in the Zone 6B region of Lancaster, PA, although the garden can have Zone 6 and Zone 7 winters. During the 2017 season, Green Leaf trialed more than 800 varieties of perennials, shrubs, grasses, herbs, and annuals. The plants were trialed in-ground, and they ranged from six months to three years old.

Trial managers do not amend the soil in the trial gardens and apply mulch only as needed. Plants are watered only if it doesn’t rain for about one week.


Sarah Mitchell, New Product Development Manager for Green Leaf Plants, shared the following information about the trials.

Variety Intake and Planting

  • We can receive material at any time of the year, in any form.
  • For vegetative varieties, we establish a small stock base.
  • Plant 21-cell liners (vernalized if needed) in the ground with a commercial comparison if possible.
    • Start planting Week 16 (mid-April)
    • Tender varieties are planted mid-May, after the frost date
    • For fall planting, we try to have everything planted by early September

Garden Evaluations

  • Ongoing evaluations, spring through hard freeze
  • Data is collected weekly or biweekly:
    • Transplant date
    • Visible bud
    • Flowering beginning date
    • Full flower date
    • Out of flower date
    • Height and width
    • Flowering height (if dramatically different than foliage height)
    • Flower size
    • Any notes about pinching, cutting back, disease, etc.
    • Plant habit and uniformity rating if evaluating a large group (within a genus)
    • Hardiness data when plants are overwintered
  • Plants are photographed throughout the season as they come into bloom.
  • At the end of the season, a decision is made to discard, elevate to potential introduction status, or to introduce.

The trial garden is open to the industry and provides an educational opportunity for customers, sales reps, brokers, and customer service representatives.

Trial Manager Favorites

Achillea ‘Ritzy Ruby’ – Deep-red flowers on mounded plants

Buddleja davidii ‘Wisteria Lane’

Dianthus ‘Vivid Bright Light’

Digitalis Camelot Series – Strong single leader followed by secondary blooms; clearly distinct colors in the series

Geranium ‘Azure Rush’ – Compact plants with blooms all summer long

Heuchera ‘Alabama Sunrise’ – Foliage is attractive all season, flowers are a bonus

Lavandula angustifolia ‘Lavance Deep Purple’ – Fast production of 1 quart pot, in flower

Nepeta faasenii ‘Purrsian Blue’ – Nonstop flowering from spring through late summer

Phlox paniculata ‘Cherry Cream’ –  Healthy, disease-free plants with excellent flower count

Stokesia ‘Blue Frills’ – Prolific numbers of beautiful blue flowers, not as delicate as they look (getting good reviews from garden writers who received plant samples this year)