The verdict’s in

There are a number of plant characteristics that are important to the end consumer, including drought and heat tolerance, as well as being pollinator friendly.

We heard from 13 trial gardens from coast to coast to discover which varieties stood up to those new challenges in their gardens, and more importantly, why. All comments come straight from trial managers.

Whether you’re simply curious, or you’re looking to add some varieties to your lineup this year or next, take note of these best-in-show options.

West Region

Best Overall Performance - Perennial

1. Dianthus ‘DEVON COTTAGE’ Pinball Wizard (PlantHaven), PlantHaven Trial Gardens

Interesting pink and white striped coloration, great cut flower, fragrant, repeat bloomer.

2. Hibiscus ‘Summerific’ Cherry Cheesecake Hibiscus (Proven Winners - Walters Gardens), Colorado State University

This perennial could be seen from a distance, standing almost 5 feet high with flowers up to 7 inches across. Peak bloom was in late August/September when plant was covered with white and red flowers. We planted this in 2014 and had 100 percent survival rate.

3. Hypericum ‘Hypearl Compact Red’ (Aris Greenleaf), Smith Gardens

This plant breaks naturally without pinching, giving it a great mounded form. The dark leaves allow the yellow flowers and red fruit to stand out. Hypearl flowered early and for months.

Best Pollinator-friendly Perennial

1. Salvia VIBE ‘Ignition Purple’ (PlantHaven), PlantHaven Trial Gardens

Vivid purple blooms on drought tolerant, grower friendly salvia. Compact tight rounded habit, 24 inches tall and wide at maturity. Well mannered. Pollinators love it.

2. Nepeta ‘Cat’s Meow’ Catnip (Proven Winners, Walters Gardens), Colorado State University

This variety proved to be the favorite for bees and other pollinators in our trials this season. Its peak bloom was in June, and it gave off a strong aroma at that time. It was a vigorous grower with plenty of flowers for pollinators. It was planted in 2014 and had 100 percent winter survival.

3. Buddleia Buzz ‘Hot Raspberry’ (Thompson & Morgan), Smith Gardens

A beautiful new color to the Buzz series. This buddleia is a butterfly magnet. A dwarf variety that is ever blooming with bright, saturated, raspberry-colored flowers.

Best Heat-tolerant Perennial

1. Gaillardia REALFLOR ‘Sunset Cutie’ (PlantHaven), PlantHaven Trial Gardens

Drought tolerant once established. Two-toned red bronze and cream bold colorfast blooms age well on long blooming plant. Very floriferous. Bee magnet.

2. Perovskia ‘Little Lace’ Russian Sage (Conard-Pyle Co.), Colorado State University

Many plants struggled in our July and August heat; this perennial survived the heat and was the largest of its kind in the trials. We planted it in 2013 and it has survived two winters with 100 percent survival over two winters and three growing seasons. It grew to about 3 feet tall and wide.

3. Agastache ‘Peachie Keen’ (Proven Winners - Walters Gardens), Smith Gardens

Most Agastache varieties will start to split and fall over in the heat of the summer, Agastache ‘Peachie Keen’ does not. We had one of the hottest summers in years here in the Pacific Northwest and this beauty flowered from June through August and looked great the entire time.

Best Drought-tolerant Perennial

1. Leucanthemum ‘Real Sunbeam’ (PlantHaven), PlantHaven Trial Gardens

Beautiful colorfast yellow, strong bloomer, early-mid summer, repeating in fall. Hardy plant, drought tolerant once established. Improved disease resistance.

2. Achillea New ‘Vintage’ Rose Yarrow (Darwin Perennials), Colorado State University

Plant proved to be vigorous, despite competing with three other Achillea varieties planted next to it. It grew to about 30 inches high, which was taller than other yarrow varieties planted in trial. It had vigorous growth and was drought tolerant, but also produced many rose and white flowers throughout the growing season.

Southeast Region

Best Overall Performance - Perennial

1. Gaura ‘Grace Blush’ (Danziger ‘Dan’ Flower Farm), Costa Farms

A low-maintenance plant that is well suited for the landscape and container gardening. The airy display of flowers lends a soft and appealing impression to any garden setting.

2. Colocasia esculenta Black Coral – Royal Hawaiian series (PlantHaven International; provided by AgriStarts), Mississippi State University

Black Coral has performed exceedingly well in full sun in our trial gardens. Planted in spring of 2014, all plants survived the winter (dormant beneath their pine straw mulch) and returned to provide a lush, tropical display of dark black leaves in 2015. Visitors love the foliage color.

3. Sedum ‘Pure Joy’ (Proven Winners), University of Tennessee

Short in stature (6 to 8 inches), ‘Pure Joy’ set buds early, and was a delight as buds opened pink in summer, forming a dense mat of blooms. Slowly over the course of the fall, they deepened to a russet color.

4. Coreopsis ‘Leading Lady Lauren’ (Dummen Orange), North Carolina State University

She performed well no matter what the condition. All the plants of ‘Leading Lady Lauren’ bloomed heavily on sturdy green mounds.

Best Drought-tolerant Perennial

1. Canna Cannasol (Dummen Orange), Costa Farms

As this is often considered a tropical plant, you may not automatically associate it with drought tolerance, but as other plants wilted in the garden, this variety stood strong.

2. Ruellia simplex Mayan White (University of Florida), Mississippi State University

This sterile form of Mexican petunia thrives in the heat can handle periods of drought, but performs best with regular watering. Spent flowers drop from the plant, unlike the old seed-producing Snow White, which tended to retain its old, brown flowers. The flowers of Mayan White also attract bumblebee pollinators. Planted in spring 2014, plants went dormant in winter and all returned in 2015 for a second year of flower production.

3. Sedum ‘Lemon Coral’ (Proven Winners), University of Tennessee

Specimens were planted next to pavement in full sun and couldn’t have been in a more challenging site, but ‘Lemon Coral’ was outstanding and caught everyone’s eye. Bright chartreuse turns to brilliant coral in fall.

Best Pollinator-friendly Perennial

1. Salvia Cathedral Shining Sea (GreenFuse Botanicals), Costa Farms

The violet-blue flowers of this perennial have always attracted attention from gardeners. Coincidentally, honeybees also found the flower to be appealing.

2. Agastache rugosa Golden Jubilee (Sahin), Mississippi State University

The light bluish-lavender flowers contrast well with the golden-green foliage, and the foliage has the bonus of a pleasant anise scent.

3. Eutrochium ‘Little Joe’ Joe-pye weed (North Creek Nurseries), University of Tennessee

Late summer bloomer really attracted pollinators but was also valued for its short (2.5 to 3 feet) strong stems that kept the plant from lodging or blowing over.

4. Salvia ‘Salute Deep Blue’ (Dummen Orange), North Carolina State University

A favorite of many of the bees and skippers.

Best Heat-tolerant Perennial

1. Ruellia simplex Mayan Purple (University of Florida), Mississippi State University

Mayan Purple has a growth habit similar to Mayan White, but with purple flowers. Plants are sterile and attract bumblebees. The hottest weeks of summer provided the most abundant flowering. Planted in spring 2014 and dormant during winter, most plants returned for a second year of evaluation in 2015.

2. Salvia greggii ‘Heatwave’ Glitter (Monrovia), University of Tennessee

Brilliant color and a long bloom time made this a choice for top perennial. Good branching habit resulted in full form.

3. Echinacea ‘Prairie Splendor Rose Compact’ (Syngenta Flowers), North Carolina State University

This variety thrived in our heat and humidity and showed off with beautiful flowers. The pollinators enjoyed it during the summer, and the birds will enjoy the seeds this winter.

4. Coreopsis Solanna Glow (Danziger ‘Dan’ Flower Farm), Costa Farms

One of the main challenges we have growing perennials in South Florida is the heat. Not many perennials can handle the high afternoon temperatures and sultry nights here, and that is why we were so impressed with the Coreopsis Solanna Glow from Danziger. Even with the midday heat, this plant did not falter in producing bright blooms.

Midwest Region

Best Overall Performance - Perennial

1. Echinacea ‘Sombrero’ Baja Burgundy (Darwin Perennials), The Gardens at Ball

Striking color for a coneflower. Plants were compact, branched well and had a long bloom season.

2. Salvia Blue Marvel (Growing Colors), Mast Young Plants

Chosen for the full habit, garden performance and large blue flowers (larger than other nemorosa type salvias).

3. Vernonia ‘Southern Cross’ (Intrinsic Perennial Gardens), Boerner Botanical Gardens

A show-stopper once it starts blooming in August. No sign of flopping over and often covered in pollinators.

4. Hibiscus SUMMERIFIC ‘Perfect Storm’ (Proven Winners), Walters Gardens

This naturally compact plant doesn’t require as heavy of PGR applications as other hardy hibiscus varieties. The foliage needs direct sunlight to develop its dark color; growing it under plastic will cause the foliage to look greener. Growing in direct sunlight is the best method for both finishing and best coloration. Starting from bare root, I grow Hibiscus ‘Perfect Storm’ outdoors and it finishes in six to eight weeks, with huge 7- to 8-inch white flowers with pink accents appearing in August.

Best Drought-tolerant Perennial

1. Verbena rigida Santos Purple (PanAmerican Seed), The Gardens at Ball

A real crowd-stopper this summer. It is very free flowering with rich purple flower clusters, and it’s never out of bloom. It keeps going until frost.

2. Perovskia Caspian Blue (Green Fuse Botanicals), Mast Young Plants

This perovskia stood out among other drought-tolerant perennials for how full it was and also for its floriferousness.

3. Baptisia DECADENCE ‘Pink Truffles’ (Proven Winners), Walters Gardens

‘Pink Truffles’ is very exciting in terms of flower color. Typically, you’ll see blue or yellow flowers on this native plant, but ‘Pink Truffles’ is one of the first on the market to bloom a soft pink. I prefer to start Baptisia in June here in Michigan, starting from a small plug and growing outside under natural conditions.

Best Pollinator-friendly Perennial

1. Lobelia Starship Deep Rose (Burpee), The Gardens at Ball

Outstanding color with a pearl-like center. Mixed well in containers and the upright blooms caught the eye in the perennial beds. Tender perennial (Zone 6).

2. Agastache ‘Little Adder’ (Darwin Perennials), Boerner Botanical Gardens

A butterfly favorite in the trial garden. This was a first-year planting, and we’re excited to see how it survives the winter and performs in following years.

3. Phlox ‘Opening Act White’ (Proven Winners), Walters Gardens

It’s the scent that’s drawing in the pollinators such as butterflies and hummingbirds. I recommend growing ‘Opening Act White’ from bare root since it yields a greater amount of stems in a short time. Along with ‘Opening Act Blush,’ these new hybrid types of phlox will bloom earlier in summer—about three weeks earlier in the ground. ‘Opening Act White’ has pure white flowers that will rebloom, especially if you sheer the plants back after blooming.

Best Heat-Tolerant Perennial

1. Gaura ‘Belleza’ and Gaura ‘Sparkle White’ (Kieft Seed), The Gardens at Ball

These lasted through the heat of the season and held their flowers, providing great texture in the perennial beds and in display areas.

2. Gaura ‘Little Janie’ (Darwin Perennials), Mast Young Plants

Flowers well all summer and has unique rosy pink and white bicolor flowers.

3. Agastache ‘Mango Tango’ (Proven Winners), Walters Gardens

‘Mango Tango’ will finish a trade gallon pot in 8-10 weeks and is relatively carefree. I love these new types of Agastaches (‘Rosie Posie’ and ‘Peachie Keen’ came to the market last year) because of their round habits and long bloom times. ‘Mango Tango’ is a darker orange than ‘Peachie Keen’ with more of a red-orange color.

Northeast Region

Best overall performance-perennial

1. Heucherella Honey Rose (Blooms of Bressingham), Penn State University

Best pollinator-friendly perennial

2. Monarda punctata BeeBop (Garden Genetics), Penn State University

Southwest Region

Best overall performance

1. Pervoskia ‘Crazy Blue’ (Darwin Perennials), Dallas Arboretum

This is one of those few perennials that bloomed starting late spring and continued through the heat of summer, requiring no deadheading or pruning of any kind.

Best pollinator-friendly perennial

2. Caryopteris ‘Blue Fountain’ (Proven Winners), Dallas Arboretum

‘Blue Fountain’ has been a top performing perennial for the past couple of years in our trials, and it is no secret that the pollinators love it too.

Best drought-tolerant perennial

3. Muhlenbergia ‘Pink Flamingo’ (Mountain States Nursery), Dallas Arboretum

Perennial grasses tend to be overlooked, but provide great options for gardens that receive little to no supplemental irrigation. The great thing about ‘Pink Flamingo’ is its vigor and abundance of bloom stalks that have the slightest tinge of pink.

Best heat-tolerant perennial

4. Achillea ‘New Vintage Rose’ (Darwin Perennials), Dallas Arboretum

Last year with a relatively mild summer ‘New Vintage Rose’ performed well, but this year was a true test with a normal Texas summer complete with multiple days well over 100 degrees. It performed just as well this year maintaining healthy foliage and loads of blooms all summer.