Discovering Alpine and Sub-Alpine Plants

Definition of alpine: The Latin word for 'high mountain' is 'alpes'. That is where today's word, alpine comes from.

The online Free Dictionary by Farlex: Alpine plants, high-altitude representatives of various flowering plants (chiefly perennials) that because of their dwarf habit, profuse blooming, and the preference of many for shady places are cultivated in alpine and rock gardens. Some species require specially constructed gardens duplicating mountain terrain, including systems for supplying cool water underground, comparable to the melting snows of their natural habitat. Others thrive without special care in favorable conditions (e.g., cool climate, short growing season, and alkaline, rocky soil). Alpine species of gentians, saxifrages, and stonecrops are among those most commonly planted. Many garden plants (e.g., roses, irises, and primroses) also have alpine representatives.

Okay, so I didn’t even try to create a mountain terrain setting, or cool underground water supply. Not even close. But I really wanted to try some of these amazing plants.

I have heavy clay soil here in my gardens, with heavy rain in the winter and spring. We have some freezing and thawing throughout winter. We seldom get snow and when it does show up it only lasts for a day or two. Forget the high-altitude, we are at 300 feet above sea level. I decided to give it a try anyway.

Imagine my surprise when I found that I was already growing a few alpine-type plants.

Anemone, Campanula, Jovibarba, Orostachys, Rosularia, Sempervivum, tulips and silene. Granted most of these are hybrids of the original species, but they have done well here in my growing conditions. In the last two years I started slowly acquiring a few true alpine plants other than the hardy succulents. I wanted something to grow in the beds with the Sempervivum, plants that would be small, provide foliage and bloom contrast, but not take over the low growing Sempervivum.

We have a total of 11 raised beds filled with compost from our local farm store. Originally all were used for vegetable beds. They grew wonderful vegetables, but the compost was not the best soil for alpine plants. Six of the beds are now converted for growing alpine plants of all kinds. I started adding sand, pea gravel and chicken grit to the compost. The soil is draining nice and fast now.  The fact that they are raised beds also helps; the amended soil sits 12” to 24” above our clay soil.

By adding a few rocks, petrified wood and other pieces of wood, I started to get the feeling of an alpine area.  Old hollow pieces of wood also make nice nooks to plant some of the shallower rooted plants.  Don’t be afraid to move things around, until you have it the way you want it.  You can also look at photos of alpine landscapes to get an idea of what you need to do.

This is a work in progress and will never be completed to look like a traditional alpine garden. It is so much fun dreaming, planning and planting, working toward creating something that will support the easier to grow alpine plants.

This spring is filled with surprises as some of these plants are coming out of dormancy. Some remained evergreen throughout the year and are already blooming, or getting ready to bloom. Spring in the alpine garden is filled with miniature plants showing off their beautiful blooms. It is an exciting thing to see.

Gentiana dinarica 'Montenegro' is a new plant that I bought last fall. It has survived our Pacific Northwest winter conditions and is looking very healthy. This Gentiana has the most amazing, bright blue color, a color that is hard to come by in the plant world. This plant will reward you with blooms in the spring and again in the late summer, early fall.

'Montenegro' also has lovely, leathery evergreen foliage, which gives year-round interest in my raised bed. I was very excited to see that it produced seed, which I left in place to see if nature will produce seedlings. 

Gentians are found in temperate alpine regions of Asia, Europe and the Americas. There are even some species in northwest Africa, eastern Australia and New Zealand. There are annual, biennial and perennial forms of this interesting plant. Some are evergreen and others are deciduous.

All Gentians have trumpet-shaped flowers that are usually deep blue or azure, but may vary from white to creamy and yellow to red. There is a red-flowered species dominant in the Andes.

Some can be very difficult to grow for the average gardener, but there are many that are easy to grow. Most will need some shade in hotter regions.

Here is a list of some of the easier to grow gentians: Gentiana acualis ‘Maxiam’ Dark blue. Gentiana acaulis ‘Sternschnuppe’, light blue, Gentiana acaulis ‘Undulatifolia’ Intense, velvet blue flowers, very adaptable, foliage is evergreen. Gentiana asclepieadea ‘Pink Cascade’, pale lavender/pink with dark stripes outside and spotted inside. Gentiana sino-ornata ‘Eugens Allerbester’, deep blue double flowered, grows in mats of grassy foliage.

Newly acquired last fall, Leontopodium 'Mt. Everest' is a Leontopodium from the mountains of Asia. It is a longer lived species than the European types and will only grow to 4 to 5 inches tall. It is also more stable in its growth habit.

Leontopodium (Greek for Lion Paw) is the scientific name for edelweiss. The genus contains about 30 species native to Europe and Asia. In the German language edelweiss means noble and white.  They are classified as a short lived perennial (generally 2 to 7 years), which will not be able to establish itself if the blooms are picked. They propagate by reseeding.

The European species can vary from one plant to the next in leaf and flower shape (very narrow to broad), height (2 to 12 inches), coloring (leaves from green to silver), blooms (bright white to grayish/green tinged).

It is a winter dormant plant that will show the tips of its green leaves peeking through the soil here in my Pacific Northwest region, until warm weather and longer daylight hours trigger it to start growing.

A list of some of the easier ones to grow: Leontopodium alpinum, the original Edelweiss from the Alps. Leontopodium alpinum ‘Matterhorn’, this one seems to have a greater tolerance for temperatures in the 90°F  and into the 100°F range. Leontopodium camtschaticum (Himalayan Edelweiss), an Asian species that grows in compact clumps; easy to grow. Leontopodium discolor, this one is native to Japan, S.E. China and Korea. It is another very adaptable edelweiss.

Polygala chamaebuxus (Shrubby Milkwort), native to the mountains of west-central Europe. It is considered a small shrublet that is easy to maintain. It is evergreen and makes for lovely winter interest in the alpine garden. Where summers are long and dry, some shade is helpful to keep it healthy. This may not be a plant for really hot climates. Zones 6 to 8.

The blooms on this plant are very interesting. The wings are white, setting the background for the keel, which is yellow. The interesting part is the yellow keel turns red with age and is very eye catching.

The buds set last fall and started blooming in late winter. This plant appears to have a long bloom season and will sometimes rebloom in summer.  It was my second plant to bloom this year, right after the Hellebores.

They may be propagated from softwood cuttings taken early in the growing season.

Another variety that has a similiar growth habit is Polygala chamaebuxus var. grandiflora ‘Kamniski’. This variety has deep purple-pink wings, with yellow keels. Very pretty.

Saxifraga is the largest genus in the family Saxifragaceae, containing about 440 species.

The Latin word saxifraga means  "stone-breaker", from Latin word  saxum, meaning rock or stone.

There are so many different types of saxifraga, that you will need to do your homework before deciding which one will fit your needs. Some are more difficult to grow than others and some grow too fast or too tall for my purposes.

I wanted those that would play nicely in the sempervivum beds, not take things over in a season or two. The ones I chose are pretty slow growing and are under 8 or 9 inches (this includes the height of the blooms). Saxifraga 'Macedonica', (synoynym for Saxifraga juniperifolia 'Adams') pictured at left, is a small leafed mounding variety with beautiful yellow blooms in late winter thru mid-spring. Another favorite is Saxifraga 'Whitehill'. The foliage is very colorful and adds interest even when not in bloom. Whitehill variety has delicate looking sprays of white blooms.

Here in the Pacific Northwest I have planted them on the northeast side of rocks or stumps of wood to give them some protection from the heat of the day. I did have one that was planted on the west side of a rock and it struggled with the direct sun during the afternoon. Moving it to a spot with afternoon shade remedied the problem.

There are some of the very tiny dwarf varieties that I would like to try, but I will have to do some research to see whether I can provide the conditions that would keep them healthy.

There are so many plants that we already have and know so well that originated in alpine regions. Did you know some tulips, daffodils, and muscari originate from alpine areas? There are wonderful species varieties of these bulbs that will grow well in your alpine garden and will benefit from the faster draining/rocky soil provided.

Have you tried herbaceous species plants like Campanula, Rosularia, Orostachys, Androsace, Sempervivum and even others? There are interesting dwarf varieties of alpine shrubs and trees that you can grow in an alpine garden.

There is a whole world of exciting plants that come from the ledges, slopes, and meadows of alpine mountains and many of them are easy plants to grow.

What are your favorite alpine plants, or which ones would you like to try? I look forward to finding more alpine plants to add to the beds this summer and fall.