By Dr. Leonard Perry
Extension Greenhouse and Nursery Crops Specialist
University of Vermont

You’ve probably heard the word “extreme”
applied to adventure activities, and many products appealing
to youth.But I like to think of it as being an appropriate
term to use with some perennials, those that tolerate
“extreme” conditions in the traditional sense
of the word.

It seems in recent years that we’ve gotten
into a cycle of extreme conditions–colder than normal
one year, warmer than normal the next winter. One summer
is hot and dry, the next cool and wet.

What’s a gardener to do? Here are six
perennials that seem to do well under variable and often
extreme conditions. Most are hardy between USDA zones
3 and 8. As a group they provide interest in the first
half of the growing season, aren’t invasive, usually
establish well, and tolerate other stresses, such as
some weeds.

Depending on your location and specific
growing conditions, not all may be suitable choices
for your garden. Unless otherwise noted, all grow best
in full sun.

Among extreme perennials to try are a
few new ornamental strawberries (Fragaria) such as ‘Pink
Panda’ and ‘Red Ruby,’ with pink or red flowers instead
of the usual white. These behave like strawberries,
even producing a few small edible fruits, but they are
mainly grown for their flowers and as a groundcover.
Flowers begin in spring and often repeat throughout
the summer.

Many perennial geraniums currently are
on the market, with more coming out each year, and are
quite variable in hardiness and other characteristics.
One that begins bloom in early summer in the north (and
may rebloom through the summer) is the Bloody Cranesbill
(Sanguineum). The first part of the name is really a
misnomer as flowers are magenta not blood red in color.
The latter part of the name refers to the seed shape.

One cultivar to try is ‘John Elsley,’
which has proven to be hardy. The small, dissected,
dark green leaves and roots withstand drought. This
cultivar usually forms a nice low mound.

Forming a much taller mound, about four
feet high and six feet across, is the False Blue Indigo
(Baptisia australis). I call it an “instant shrub”
as this is how it appears by early summer with dark
blue flowers, followed in late summer by black seed
pods. The latter persist through winter, creating great
seasonal interest in the garden.

A relatively new perennial is Alexander
Loosestrife (Lysimachia punctata), which is quite different
from the other plants of this species. It has creamy
margins on the variegated leaves. It withstands drought
fairly well with less wilt and browning of leaves and
appears equally as hardy as the rest of the species.
This loosestrife forms a nice clump (about 18 inches
high) and doesn’t spread invasively. Yellow flowers
appear in early summer.

Daylilies are one of the lowest maintenance
perennials for the garden, with a range of colors and
thousands of cultivars. Many have flowers with exotic
fringed petals and bicolors, making them quite different
from the orange “ditch lily” most people are
familiar with which grows along roadsides. Some “evergreen”
types are better in the south, but most do well north
or south, and in variable conditions.

Some may get some leaf streaks on leaves
in late summer or distorted growth early in the year
(“spring sickness”), but daylilies seem to
come back and bloom each year. If severe drought, some
lower leaves may yellow and brown but can be just pulled

If you are looking ahead to next spring,
consider planting daffodils this fall. I love daffodils,
and plant more each September for early spring bloom.
You can choose from many new cultivars, with some blooming
early and others later on in the season. Once planted,
they can be left alone, and usually aren’t bothered
by rodents and small mammals.

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