Using Bare Root Plants

Over the 5 years or so that I've been here in Pleasant Valley (Zone 6b) I've been augmenting our grounds with more native species.  In order to get some of the species I wanted I've been getting more bare root plants than in the past.  What I like about them is that you can find many species that are not available in containers and that they are much less expensive, averaging about 1/3 the cost of the same plant in a container.  This lower cost is due in part to the lower costs of shipping, only the plant without the soil, and to lower production costs at the supplier.  The down side is that these plants are only available when they are dormant and that they need to be planted while it is still pretty chilly out, either in late fall or very early spring. So right now (January) is a great time to get in an order, in time for early spring planting.

I've had mixed success with these bare root plants.  Reasons for failure include not planting them in the right place, competition from existing plantings, deer browsing and some poor technique.   I won't go into the steps of planting bare root plants, they often come with detailed care and planting instructions.  You can also find instructions on the web. 

Here are some things I've learned from my experiences:

Get plants in the ground quickly.  If possible get them in the ground within a day or two of when they arrive.  While you can keep them in cool storage for a time as long as the roots stay moist, or you can heel them in, by laying them in a shallow hole and covering the roots with moist soil.  I seem to be having better results with plants that I put in place quickly.  It is important to get plants in the ground while they are still dormant.  This way roots can get in good contact with the soil before the buds open and put a greater stress on the plant.  I have planted bare root stock in both late fall and early spring.

This Canaan fir has been in the ground for about 2.5 years. 
It started at about 6 inches.  The chicken wire and steel posts help
protect it from male deer who will rub off the branches
as they clean their antlers.

Get good soil contact with the roots.  When planting in the garden make sure that soil is well packed around the roots and spread the roots out in the hole as you layer in the soil.  What I have been doing lately is carefully spreading out the roots as I have been adding in the soil.  After about half of the hole is filled I fill the hole with water and let it settle.  This removes air pockets and improves soil contact with the roots.  I continue to fill in around the plant with soil, continuing to spread out the roots, followed by another through watering. 

Plants in pots need time to develop a good root system.  For bare root plants that I haven't had time to plant, I've potted up with container mix, watered them well and left them in a cool protected location.  Only about half of the plants survive until the weather warms up.  Not a particularly good record.  The survival rate of these potted up plants after transplanting has not been great either.  What I believe to be happening is that the roots have not had a chance to develop while in the pot and there is too much damage done to these weak roots when they are transplanted into the garden.  I've had better success with plants that I've allowed to grow in the pot for a full season before going out in the yard.

Protect plants from critters and competition.  I've lost a number of young plants to deer browse, so now I put a little chicken wire cage around most of my new plants.  I've also lost a number that have been shaded out by surrounding vegetation.  When planting in mid-fall or early spring it is not obvious how much crowding there will be come June and July.  I need to remember that these are still little plants and they are easily over-shadowed by larger established vegetation.  Like any new plant, bare root plants need extra water while they are getting established.  I also tie a fluorescent pink ribbon around each new plant so that I can locate them more easily when clearing out the competition.

Close examination of this Juneberry shows that the leaf buds
are still plump and healthy looking.  A good sign
that it will survive the winter.  The pink ribbon helps me keep
track of these new additions in the landscape.

Here are some of the species I've worked with:

Here is the Twinleaf in bloom.  This is one of the first bare root plants
I put in.  It's now 4 years old.

Perennials:  Celendine poppy (Stylophorum diphyllum), Christmas fern (Polystichum acrostichoides), Merrybells (Uvularia sessilifolia), Twin leaf (Jeffersonia diphylla),and Jack in the Pulpit (Arisaema triphyllum) have performed quite well.   Mayapple (Podophylum peltatum) and  Large-flowered bellwort (Uvularia grandifolium) are in dryish soils and have been struggling.  The wild ginger (Asarum canadense) was planted in a very challenging location, under an English walnut and surrounded by vinca, and has faded away. Alleghany pachysandra (Pachysandra procumbens) was planted in November in a dry shady location, so we'll see how that works.

Shrubs:  Black chokeberry (Aronia melanocarpa),  Gray dogwood (Cornus racemosa),  American hazelnut (Corylus americana), Witchhazel (Hamamelis virginiana), Spicebush (Lindera benzoin),  Chokecherry (Prunus virginiana),  Smooth sumac (Rhus glabra), Red elderberry (Sambucus pubens),  and Meadowsweet (Spiraea alba v. latifolia).  The meadowsweet and hazelnuts have been the most successful at getting established.  Smooth sumac has suffered from both deer browse and being over shadowed by other aggressive plants.  The red elderberries and witchhazel which did not make it were in very shady spots.  The chokecherries were potted up when they got here and only 2 of the 6 survived.  Those 2 were planted out 3 months later.  Soon we'll see how they made it through their first winter.   

This American hazelnut has been in the ground
for about a year now.  In the inset you can see the swollen leaf bud
that indicates that this branch is still alive.

Trees:   Canaan fir (Abies balsamea v. phanerolepis),  Concolor fir (Abies concolor),  Juneberry (Amelanchier canadensis),  Redbud (Cercis canadensis), Red cedar (Juniperus virginiana), Tupelo (Nyssa sylvatica),  Virginia pine (Pinus virginiana), American plum (Prunus americana), and  Douglas fir (Pseudotsuga menziesii) .   The best performers of this group are the tupelo and the Douglas and Canaan firs.  Ones that have not worked out here are the Virginia pine (wrong soil type here), Redbud (location had too much shade from competition), Red cedar  and  the Concolor fir (uncertain).  The American plum was just planted this fall, so the jury is out, but they look OK so far. 

Native Plant Wish List for 2014

With a new planting season approaching I am planning on continuing my crusade to replace  the invasive species with native, mostly indigenous, plants.  I have another round of brush clearing to do this winter, especially the removal of some Autumn Olive tree/shrubs.  I am also looking to reduce the number of Butterfly bushes and Forsythia on the property and replace them with higher value native shrubs. 

Over Christmas I took the time to finish reading Designing Gardens with Flora of the American East, by Carolyn Summers.   The chapter on 'showy substitutes for invasive plants' was very inspirational in making up my plant list for this season.  This book is an excellent resource for anyone interested in designing native plant gardens.  There is sound reasoning behind each of the recommendations in this book.  I found this to be  much more useful than just a list of what should or should not be done when designing a garden or landscape.   To enhance the wildlife value of our property I am trying to  use a combination of plants that have something in bloom throughout the season for the pollinators as well as berries and fruits for the birds and small mammals.

Anyway, here's a list of my target plants for 2014:

Pussy Willow, Salix discolor.  I was surprised that this is a native species.  I is used so commonly in early spring decor that I figured it had to be imported.  The catkins swell in very early spring, first as white, silky buds, then opening to reveal either yellow (male) or greenish (female) flowers.  Pussy Willows are dioecous, male and female flowers are borne on separate plants.  My plan is to use the pussy willows as replacements for Forsythia.  The color intensity will be much less, but the wildlife value will be so much higher with the willow.  For all its flowers, I have seen very few bees visiting a forsythia in bloom.    Pussy Willows like full to part sun and prefer moist soils but will tolerate some dryness.  They are larval hosts for Viceroy and Mourning Cloak butterflies and they tolerate deer.  

I'm not sure of the exact species.  This photo is from the end of March in Boston.

I took this photo of a shrubby willow at the Arnold Arboretum about 5 years ago.  I did not record the name at the time.  As I was trying to find out more info about it, I went to the arboretum's web site and found that they have actually made an Internet accessible map of their plantings.  Using that map and my memory of where I took the photo, the willow in question is either the native Bebb's Willow, S. bebbiana, or an introduced Black Willow, S. gracilistyla 'Melanostachys'.  Based on the light color of the catkins, I guess that it's the former.

Another substitute for Forsythia is Spicebush, Lindera benzoin.  Its flowers impart a yellow haze to the forest understory about the same time as the Forsythia are in bloom.   It grows better in shadier situations than either Pussy Willow or Forsythia. 

For a partly shady area I would like to try replacing the Forsythia with Red Osier Dogwood, Cornus sericea.  This plant is in bloom from mid-late May and follows up with nutritious berries in mid-late summer.   Besides the flowers and fruits this dogwood also has purplish fall foliage and red-colored stems in winter, features definitely lacking in the one-trick pony, Forsythia.  Species plants can get large (6-10') but there are compact cultivars like 'Isanti' and 'Arctic Fire'.  A big problem with dogwood is that deer find most of the plant pretty tasty, but I have seen large plantings doing well along the roadsides.  This dogwood serves as the larval host for the Spring Azure butterfly.

This 'Isanti' cultivar is in full bloom at the end of May and should grow to about 6 feet.
Cutting back the older growth each year will keep the size down
and give more new red stems in the winter.

As far as replacing the Butterfly Bushes, Buddleia davidii, a multi-shrub approach may be needed.  Butterfly Bush has a long period of bloom and is very attractive to pollinators.  But it's like candy.  The plant does not act as a host for any native insects.  Thus, as it displaces native species, it excludes useful host plants, and degrades the habitat value of the garden.
 

The seed heads of Sumac make them easy to spot.  Not sure which species this is.
The stems of R. glabra are smooth, while those of R. typhina are hairy.

For the early part of the summer I am looking to Smooth Sumac, Rhus glabra.  This is also a common roadside plant, but not so common in the nursery trade.  It's chartreuse panicles do not stand out to humans, but they do to butterflies.  What is most noticeable in this shrub is the scarlet fall foliage and the deep red berries through the fall and winter.  It grows to about 15 feet, similar to many of the mature butterfly bushes around here. The larvae of the Hairstreak butterfly use Sumac as host plants.

For  the second part of the season I will put in some American Elder, Sambucas nigra ssp. canadensis (often S. canadensis).  American Elder likes medium to moist soils and part to full sunshine.  I have seen this growing in roadside ditches covered  with white umbels in the middle of summer.  Dark, palatable berries follow in early fall.   This shrub does not have a neat compact form, but neither do most forms of Butterfly Bush.  I am somewhat concerned about deer browsing on the young plants, so some protection will be needed. 

This native Spiraea blooms throughout the summer
and is a magnet for bees.

Other shrubs that provide mid and late summer flowers which  I put in last year include dense St. John's Wort, Hypericum densiflorum, and Meadowsweet, Spiraea alba var. latifolia (this one blooms all summer long).

In the areas where I have cut down the Autumn Olive, Elaeagnus umbellata, I am looking for native plants to provide lots of mid-summer  flowers, a large crop of fruits, and fairly dense branching to provide cover for birds.  Cockspur Hawthorn, Crataegus crus-galli, looks to be a good fit.  It blooms through mid-June and has lots of berries from late summer into winter.  It has dense horizontal branching and long thorn that provide a lot of protection for birds.  (For use closer to people there is a naturally thornless variety, var. inermis.) 

I would also consider Chokecherry, Prunus virginiana, while blooming earlier, it is faster growing and has fewer disease problems.  Chokecherry lacks the thorns of Hawthorn, but can form a thicket-like colony.  Looking in Douglas Tallamy's book Bringing Nature Home,  the cherries are near the top of the list as far as their ability to support butterfly species.  Hawthorns come in 12th, both way ahead of an invasive species like Elaeagnus. 

'Blue Muffin' is noted for it's sapphire berries,
as long as there is another Arrowwood around for pollination.

The other shrub that I will be putting in place of the olives is Arrowwood Viburnum, Viburnum dentatum.   These bloom in late May through mid-June and produce dark blue berries from late summer through autumn.  As I have mentioned before in this blog, Viburnums are self-sterile, so you need to have more than one genetic individual of each species to get berries.  Fortunately a local nursery is offering seed grown, wild-type plants so I won't have to worry about self incompatibility.  Wild-type Viburnums can get too large for many landscaping situations.  There are a number of more compact cultivars for garden use, such as the 'Blue Muffin' (aka 'Christom') shown here.  Together the Viburnums and the Hawthorn or Chokecherry will provide a nice edge habitat for with both food and shelter for wildlife.