Archive for Shade groundcovers

Designers List of Shade Plants for Root Weevil Resistance

NE Portland Hostas with Root Weevil Damage

Root weevil damage distracts from an otherwise beautiful collection of shade loving plants.  

Designers List of Shade Plants for Root Weevil Resistance

Root weevil disfigure so many shade garden plants and can make a garden look ravaged. It’s disappointing to see hosta and other plant leaves looking all chewed up. Can we design a shade garden with beauty and style without using root weevil favorite snack plants?

“Well HELL that’s not much of a shade garden” is what I said after eliminating plants root weevil like to eat. I was disappointed in the tiny number of plants that would work and wandered off to write about something different, something a bit cheerier!!!! However, I’ve been thinking about it and yes, we have some great plants we can use. 

Evergreen Shrubs  

Fatsia japonica Spider's Web in SE Portland Residential Landscape Design

Sometimes choosing an interesting variegated leaf, such as this Fatsia japonica ‘Spider’s Web’ can hide the notching caused by Root Weevil (look close!)

Aucuba, Daphne and Fatsia are not root weevil favorites and if you select the variegated forms the notching doesn’t show as much. To be specific, Daphne odora ‘Marginata’,  Fatsia japonica ‘Spider’s Web’, and Aucuba japonica ‘ Gold Dust’ are varieties that I recommend.

I have never seen much leaf damage on our Native Huckleberry (Vaccinium ovatum) probably because the leaves are so tiny.  It doesn’t show which is what we are after.

Three Root Weevil Resistant Rhododendron for Part Shade 

Grant Park Garden Design Rhododendron with Root Weevil resistance

The fuzziness on the bottom of the leaves on some Rhododendrons reduce Root Weevil damage.

I’ve found  lists of root weevil resistant rhododendron less than helpful since most Rhododendron listed are sun lovers. Root weevil prefer part shade to shade loving plants.

Rhododendron ‘Clipiense’ is my best weevil resistant compact rhododendron for shadier situations. This rhody has fine hairs on the leaves so root weevil rarely bother it. It’s a slower growing variety and can take more shade than the other two I have listed but not deep shade.  Any rhododendron with a hairy or fuzzy leaf will be root weevil resistant.  Many of the hairier leafed plants are sun lovers but not all.

Rhododendron ‘Sappho’ is a tall white flowered w burgandy splotched flower.  Sappho does well in morning sun, dapples and afternoon shade.  

Rhododendron ‘Blue Diamond’ can take full sun but does well in full am sun and afternoon shade. It can get taller than wide.

Perennials   

NW Portland Sword Fern and Hardy Geranium in Residential Landscape Design

Sword fern (Polystichum munitum) and Hardy Geranium (Geranium macrorrhizum) do not show Root Weevil damage.

Sword fern (Polystichum munitum)  has a fuzzy frond (leaf) and root weevil don’t eat fuzzy leaves typically. Most fuzzy fronded ferns will be root weevil resistant and are an important player in a root weevil free planting. 

Hellebore argutifolius is perfect for NW Portland Landscape Designs

Helleborus argutifolius photo credit: Great Plant Picks

Hellebores are typically safe from weevil once they are mature plants. When the soft and munchable new leaves unfurl in February the root weevil have not hatched yet (here in Portland) so are not present until late April or May. The harder leafed hellebores like Helleborus argutifolius seem particularly impervious. 

Groundcover Plants   

Oregon Oxalis (Oxalis oregana) doesn’t seem to get a lot of weevil attention in my gardens and it is fun to add to salads. Same with our native piggy back plant Tolmiea menziesii. It has hairy leaves and is great for shade. For Saxifraga varieties, use the hairy leaved varieties for weevil resistance, the smoother ones are on the weevil munch list. Hardy geranium varieties that smell like cedar and have a fuzzy leaf are 100% weevil resistant – Geranium macrorrhizum for deep to moderate shade and Geranium x cantabrigiense for part sun areas. Another good bet is Sweet woodruff (Galium odoratum)

Last but not least, Euphorbia Rob’s spurge (Euphorbia amygdaloides var. robbiae) is a tough evergreen ground covering shade plant. I consider it a thug but it’s great to use in gardens where I have a path that doubles as barrier to their creeping roots. This plants roots must be contained or it will march right over your hostas. I’ve never seen any root weevil damage on this plant.

 Know Thy Enemy?   

Root Weevil have no natural predator here in the Pacific Northwest so it’s rare to find a shade garden without them.  We can cut the population of root weevil down to tolerable numbers and thus get our beautiful shade garden back. Read my blog “Attack of the Root Weevils”  to learn what can be done to reduce their population in your garden. 

 

Deep Shade Plants Tried and True

Deep Shade Plants Tried and True

Garden Design Northwest Portland Fatsia Japonica, 'Spiders Web'

Large leaves of Fatsia Japonica capture the available sunlight efficiently.

How to Select Plants for Shade

Let’s look at a handful of plants.  Most of these plants can take a little sun but my point is, they  can thrive in deep shade which is a difficult  area for many homeowners to select plants for.

Selecting Shade Plants

Tip:  Think about it…big leaves are like big hands. The more surface area the more light the plants can access. Having said that……this is a perfect example of the rule about how there are no steadfast rules. Our native huckleberry, Vaccinium Ovatum has tiny but highly reflective leaves, (such a rule breaker!) and yet it grows very well in a lot of shade.  Sigh…plants are tricky.

Tip:  If you have the luxury of planting your mostly shade tolerant plants where they get good dapples of sun of even morning sun they will often tolerant the shade deepening over the years.  If your shade is very dark now there are some plants that will eventually thrive but they may take many years to fatten up and fill in.  Add one or two very active dogs to this mix and these plants will not survive long enough to do you proud.

Small Trees for Shade

Plant this beautiful Snake Bark Maple under your fir trees….Acer Tegmentosum “Joe Witt”  Manchurian Snake Bark Maple

I have great success with a small tiny leafed evergreen tree called Azara microphylla in deep shade and also partial shade under big fir trees. I saw a tree at an abandoned property in Raleigh Hills where it was providing privacy between neighbors.  It had not been irrigated in at least 3 years and was competing with a Douglas fir tree as it was planted about 8′ off the large trunked tree.  I’ve been a fan every since and use this small tree large shrub in my city landscapes in N. Portland and N.E. Portland often because it provides privacy but doesn’t get too big.  My lousy photo does show the general shape so you can see what a great screen tree it could be.

Shrubs for Shade

Fatsia Japonica  (also called Japanese Aralia)  This is beautiful planted as under story to larger trees. It is also my 3 Labrador dog yard plant so very tough and can take a fair amount of morning sun.   It can grow to be a 15′ tall tree although it is rare to see it this way.  It is easy to prune so can be kept as an evergreen shrubs 3 to 6′ tall or can tolerate deep shade, morning sun or even afternoon dapples of strong light.  Tip:  Some shade plants can take quite a bit of sun.  Many will tip burn the first year or two but go on to tolerate a lot more sun than you might think.  Careful watering will make the difference between a guess and a plan.

Aucuba, also called Cast Iron Plant is typically used in deep shade.  It has toxic berries so is not a favorite for back yards with dogs although I have seen many old plants grow into small trees and no ones dog has ever bothered to eat the berries.  Still who wants to take a chance with their little bundle of joy and I do not trust Labradors among other breeds who seem to think everything should go in their mouth.

Native Plants for Shrubbery

Mahonia Nervosa and Vaccinium Ovatum are both shrubs native to the Northwest.  The Mahonia, (also called Oregon Grape) a favorite of hummingbirds, can get a little ratty looking at the end of winter, wait until the hummingbirds have gotten their fill of the flowers and then cut the plant back to about 12″ tall every year.  There won’t be berries for birds if you do this but you can keep the plant front yard attractive.  You won’t get a lot of flowers in deep shade.  I like growing this plant in enough sun to increase flowering for both pollinators and food for birds via the berries.  http://www.greatplantpicks.org/plantlists/view/980

Shade Plant Huckleberry in NW Portland garden with red cushioned stump chairsOur evergreen native Vaccinium, a huckleberry plant will be more shade tolerant if you buy it from Boskey Dell Natives and ask for one that was dug out of deep shade.  I have  self seeded native huckleberry at my home on the Puget Sound in a lot of sun. The truth is the offspring of my plant (little rule breakers) will prefer a sunnier location than if planted in full shade. This is all about natural selection and where your plants seed came from.  When I put it on my plant list I don’t require it come from a shade area and it has worked out quite well for my gardens.  Please note you won’t get much fruit growing this evergreen in deep shade.  My photo is from a tour of the home of Joy Creek Co founder Maurice Horn and his family.  He used the huckleberry shrub as a back drop for a casual sitting area.

Here is a highly textural native fern called Adiantum Aleuticum, Northern Maidenhair Fern. This one has previously escaped my radar. I use a lot of different ferns so nice to have another native one to use.

Ground Cover Plants for Shade

Evergreen plants for shade  – Perennials and Groundcovers

These first two are a little more unusual (unless you are a total plant nerd).  Beesia Deltophylla, I first met this plant at the famous Heronswood Garden in Kingston, Washington. It is slow to bulk up but is such a low maintenance plant. It would be great to have more access to this plant. When I first wrote this blog in 2012 it was hard to find but now I see it regularly at many retail garden stores. It won’t flower well in deep shade but the glossy leaves reflect light and are a huge asset in a deep shade setting.  It will flower in dappled shade and rather nicely.

Begonia grandis flowering in September

Selecting Shade Plants Begonia grandis is very attractive

Begonia Grandis leaves in late spring

Begonia grandis – ok this won’t survive the big rowdy dogs but wow it is a cold hardy evergreen perennial with fabulous leaves.  The flowers are also attractive.  I’m very fond of this plant and have it coming back every year in many gardens.  It rooted into a log just under my floating home and lived for several years until a certain someone thought it was a weed and yanked it.

Geranium macrorrhizum is a groundcover shade plant that may take a while to bulk up in deep shade but it will get there.  The strong smell of cedar in the leaves tends to keep rowdy dogs out of it so the survival rate is strong but it is not a thug and will slowly clump to cover a lot of soil.  It is semi evergreen so you will have some leaves in the winter too.

Shade plant in Irvington neighborhood handles shade and big tree roots too.The best fern for deep shade is our native Sword fern, Polystichum munitum but another option for shade is this non native often called Shield fern.  It will take a lot longer to establish than our good old Sword.   Sword fern can also handle a lot of doggie rowdiness , (even in shade)  if you start with a nice big plant.  I’m feeling unfair to other ferns because I always talk about Sword Fern and how fabulous it is.

We would love to help you with your shady landscape.  Contact us if you are ready for help with your difficult shady and probably muddy back yard.