Question
QUESTION: In hopes of forming a shrub screen we planted containers of Lilac Dogwood Burning Bush and Ninebark in mulitples. It's been a few weeks and they look fine (although the burning bushes look like slackers compared to the rest). I wondered if I should be giving them something additional like food or fertilizer. Also what's the best mulch variety for them? We have had a lot of rain and I water when regularly.
Susan

ANSWER: Please tell me if I understand you correctly: You recently planted, in the ground, container-sized Lilac (Syringa), Dogwood, Burning Bush and Ninebark.  They are planted fairly close because you intend for them to grow into a thick privacy screen.  You prepared the Soil where they would be transplanted, and dug the typical $10 hole for the 10 cent shrub.  You watered them thoroughly after they were set in the ground.

Do these shrubs/trees get a full day of strong Summer Sun?  Or is there are large tree or building that blocks full Sun rays from the plants?

And where do you live?  Juneau Alaska?  Boise Idaho?  Paris France?  rsvp

THE LONG ISLAND GARDENER

---------- FOLLOW-UP ----------

QUESTION: Thanks for your reply. You are correct and they get full Chicago sun. I have found that the Dogwood needs more water than the others, a circumstance that mulch would probably help.
Susan

Answer
You pose a complicated question here, and I hesitate to answer because you are combining four different plants with some comflicting cultural standards.  But you've waited patiently, and this is a serious project you are working on.  So here goes.

The operative word here is Complicated.

Lilacs are alkaline-soil shrubs, not dense enough to work as a privacy hedge but grown best in groups and ideally positioned a distance from a house or garage.

'Ninebark' (Physocarpus opulifolius) is a very cooperative, undemanding shrub famous for its fascinating, peeling bark (when grown successfully), and makes a very good privacy screen.

Dogwoods need Soil on the acidic side, and some -- Cornus sanguinea for instance -- make a very good hedge.

The most popular featured of the 'Burning Bush' (Euonymus alata ) is its brilliant crimson leaves in Autumn; it adapts to a wide range of Soil and light situations, and can be pruned or grown as a specimen.

One complication here involves something we didn't even know about 20 years ago: Different Mycorrhizae.  These are specialized Fungi that develop over time around roots and serve the same functions as a highly efficient network of extra roots -- and they burst into action because plant roots secrete chemicals that trigger a break in dormancy of Fungal spores that particular plant likes best.

In fact, when you transplant one of these shrubs or trees, the so-called 'shock' is actually the plant's reaction to losing its connection to these specialized Mycorrhizae/Fungi.

Still with me?  New science here.  21st-century technology and discoveries.  We're not in Kansas anymore.

Trouble is, the plants don't like the same Mycorrhizae.  They like specific Fungi.  Different strokes for different folks.  Packing four different Mycorrhizae underground to build up the roots is asking a lot.  A single species would have been much easier on the roots.

One advantage that figures prominently in the benefits of Mycorrhizae is that they make plants they are hooked up with INCREDIBLY drought tolerant.

Cornus 'Ivory Halo' was grown with and without these specialized Fungi in one study posted online that was conducted at Canada's CropHealth Advising and Research for a regional meeting of the Int'l Plant Propagators' Society two years ago.

And since a picture is worth a thousand words, take a look at the pepper plants in their experiment involving those with and without Mycorrhizal Fungi, deprived of water, all pictured here:

www.ipps.org/WesternNA/wr2006/Presentations/Lanthier1.pdf

Fortunately, there is a company that makes a line of Plant Care Products that are right up your alley: TreeHelp.

Given the myriad and sundry needs of this very complicated privacy hedge, I would review their catalog and perhaps even contact them to see what specifically you can use to optimize health of these plants:

www.treehelp.com

They actually have a product specifically for Dogwoods:

www.treehelp.com/itemdesc.asp?ic=TR-DOG-M

Understand that Treehelp doesn't have a monopoly on this stuff.  Espoma and many other companies make it, and Mycorrhizae grow naturally in your Soil UNLESS you destroy them by Rototilling, sterilizing, Fungiciding or otherwise disrupting them.  The treatments you purchase however will expand the populations quickly, which means your plants benefit from them faster.

Can you see how much more efficient and effective it is to have Mycorrhizae in your Soil, feeding roots out of a vast network of connections?

MUCH better than traditional chemical fertilizer.  Which by the way wipes out many microbes in a single application -- all those Salty Chemicals cause SO much underground Angst.

So now that I sound like a commercial for the Mycorrhizae companies, let's get to the matter of Mulch.

Mulch is great -- if it's the right Mulch.  It should support development of a healthy Mycorrizal population.  Mulch can do that.  Jeff Lowenfels explains this in a chapter on this very subject in his book, Teaming With Microbes.

'Mulch provides nutrients and a home for certain soil food web organisms,' he notes.  A mulch of aged, brown organic materials suports Fungi; a mulch of fresh, green organic materials supports bacteria.  Mulching your garden with brown leaves will encourage a flush of Fungi.'

At the top of his mulch list is Autumn leaves.  "Leaf mulches grown more Fungi (or at least grow Fungi faster) than do Wood chips,' he says.

Peatmoss is a popular Brown mulch.  But right out of the bag it lacks microbes.  It must be mixed with Soil, Compost or Humus to serve as a growing medium for the Mycorrhizae that are so good for your shrubs.  It is probably inferior to Leaf and Wood Mulches.

Pine needles must never be used; ditto, Cedar chips.  Both have oils which 'contain high levels of Terpenes' -- mild poisons that discourage competition from other plants.

Other Woods make fine Mulches, he says.  Larger chips break down slower, which is not only more convenient but promotes growth of the Mycorrhizae that boost plant health.  The perfect combination, Lowenfels says, is to place a layer of Compost down first, then pile the Mulch over it.

'A 2-inch layer of bark chips will last about three or four years, as the Lignin, Cellulose and waxes in the bark are difficult for microbes to decay.  During this time, Fungi will dominate,' Lowenfels writes.  The long term defense against Weeds is based on the vast amounts of Nitrogen consumed by microbes in a Wood based Mulch; Weeds don't stand a chance in that kind of environment.  Make sure the Mulch is no thicker than 3 inches, and avoid piling it around the main stems near the ground, where it might damage them.

Finally, be vigilant about watering in early weeks of this Summer-planted hedge.  Roots are still raw; there are no Mycorrhizae right now, and root hairs are recovering from transplant.  They will tend to wilt easily.  At the same time, you must not over-water -- the most common cause of transplant failure.  This is a real balancing act.  Good luck with it, and keep me posted.

THE LONG ISLAND GARDENER