A lecture to pass along some basic knowledge of pruning

1. EVERYTHING YOU EVER WANTED TO
KNOW ABOUT PRUNING…
BUT WERE AFRAID TO ASK
Basics for residential light tree, shrub and perennial
pruning.
Jeff Griff
President Lowe’s Greenhouses
YOU’RE JUST A SNIP AWAY FROM PERFECTION!

7. BEFORE I
FORGET…

8. In my experience,
working in the
garden center, the
most frequently
asked questions are
about pruning.
Why do you think
that is?

9. They say that the most common fear is
that of public speaking …

10. …followed closely by the fear of killing
your plants by pruning incorrectly!

11. Now, of course, you are an
exception to the rule being
gardening experts. I would
guess that you actually like
to prune and enjoy this
leisure time activity.

12. The reality is that, typically, when we offer pruning
classes, it is generally populated by women who
then….

13. …send this guy out to
do the pruning.
Few homeowners
understand pruning
and, unfortunately,
many landscape
professionals lack this
skill as well.

14. The fear of pruning is
so prevalent it has
even been featured in
many Hollywood
motion pictures.

16. 17650 Elm Street

18. #1 Light tree pruning and young tree training
#2 Shrub pruning
#3 Perennial pruning

19. But let’s be
realistic!

20. Pruning is an art form that can’t be
simply communicated in a classroom
setting. It is a lifelong pursuit of
gathering a combination of plant
knowledge as well as gauging
cause/affect results from various
techniques, timing and ever-changing
environmental conditions.

22. #1 LIGHT TREE PRUNING
(AND YOUNG TREE TRAINING)
Pruning is not like Red Bull…
it does not give you wings!!!

23. The first thing to know is your plant’s tendencies. What
is its natural shape and growth rate? What are its
features and benefits.

24. What are we looking to do?
*Remove dead, damaged or diseased branches.
*Enhance tree structure and reduce risk of future branch
damage/failure.
*Promote healthy and attractive growth.
*Enhance flowering and/or fruit production.
*Eliminate rubbing/competing branches.
*Remove co-dominate stems.
*Extend life of landscape plants.
You may end up finding this information most helpful
when selecting new tree specimens.

25. When is the time to prune?
What is the desired effect?
*Maximize growth: in early spring.
*Minimize risk of pest and decay: during
dormancy.
*Minimize effect on fruit/flowers:
immediately after flowering.
***Timing may not be an option when
pruning storm damage or when
eliminating hazardous branches.

26. STRUCTURAL PRUNING
*Removing dead, broken or
damaged branches.
*Selecting a dominate leader or
multiple strong leaders . (not all
trees have a central leader)
*Select the lowest permanent
branches.
*Select scaffold branches that
are spaced evenly both vertically
and radially.
*Identify temporary branching
for energy production and
protection.
***Do not remove any more
than 25% of a tree canopy per
season.

29. CODOMINANT STEMS
*Are forked branches of similar size lacking a normal
branch union.
*Frequently forms a weak point of tree with included
bark. (Bark embedded in crotch of tree)
***Not all trees have a single dominant leader.

31. CROWN CLEANING
*Removing dead, diseased, rubbing, competing and broken
branches.
*Cleaning can be done at almost any time of wear.
CROWN THINNING
*Removal of branches to improve light penetration and air
circulation.
*Reduces risk of storm damage.
*Shows off trunk form and/or attractive bark.
*Be careful not to be too aggressive.

34. Much of the most important pruning on trees will be done
when they are very young so selection and training are very
important for a long and care-free life.

35. #2 SHRUB PRUNING
GOOD

36. *Shrubs stand to gain the most from proper pruning techniques.
*Fast pruning is easy to learn, easy to do and easy to sell.
*Pruning is often done in late summer when it is convenient for
landscape companies. (A perfect time to cut off newly formed flower
buds.)
*Proper pruning takes time, patience, knowledge and (when done
correctly) is not easily detected.

37. Remember…good pruning cannot
make up for bad design!!!

38. PRUNING LAWS, PRACTICES, PRINCIPALS AND…
OTHER STUFF
*Pruning stimulates growth from the point of pruning.
*Shearing and pruning are not the same.
*Prune spring flowering shrubs immediately after flowering.
(Flower buds are formed during previous summer)
*Prune summer blooming shrubs during dormancy.
*Trimming can be done any time.
*Know what plants bloom on old growth and new growth.
*Know your plants. Consider getting professional assistance
to help identify your specific pruning needs.

39. How are your shrubs are like Olympic athletes?

40. You have to know what
kind of shape you’re in!
It is to your and the
plants benefit to
accentuate natural
plant growth instead of
fighting against it.
Another very important
detail is to understand
your plants potential
growth rate.

41. Gold Mop
Cypress

42. A 40 year old landscape planting.
There is only 1 pruning method that is effective in this scenario!

43. DO PLANT TAGS LIE?
Now let’s look at some shrub pruning techniques.

44. THINNING OR GRADUAL RENEWAL PRUNING
Examples of common shrubs that benefit from gradual renewal or
thinning:
Aronia, Clethra, Deutzia, Forsythia, Itea, Lilac, Mockorange,
Potentilla, Spirea, Viburnum, Weigelia.

45. NOT SO GRADUAL RENEWAL PRUNING
Shrubs that generally respond well to complete renewal pruning:
Aronia, Clethra, Cornus (shrub forms), Deutzia, Forsythia, Hydrangea
paniculata, Itea, Mockorange, Potentilla, Privet, Spirea, Taxus,
Viburnum, Weigelia.

46. SHEARING
Common shrubs that are often sheared:
Azalea, Barberry, Boxwood, Burning Bush,
Forsythia, Hibiscus, Lilac (Dwarf), Privet, Taxus.

47. HOW HARD DO YOU WANT TO WORK?

48. HOW DO YOU HEDGE?

49. Sheared plants need
to be periodically
thinned to allow
light to penetrate
the outer shell of
foliage.
As a rule, shear
twice, prune/thin
once.*
(*Ideally done in
late fall to allow
snow penetration)

51. AND FINALLY… THE MOST FRQUENTLY
ASKED QUESTION ABOUT PRUNING IS:

52. Hydrangea paniculata (Cone shaped, summer flowers)
Easy to bloom, hard renewal prune in dormancy.
*Trimming a 2nd time in early summer can also be
helpful in certain situations.
*Certain cultivars respond better to mid-season
trimming.

53. Oak Leaf Hydrangea quercifolia (Large leaves, summer bloom)
Thin as needed or prune hard to renew.

54. Hydrangea macrophylla (Big leaf Hydrangea)
Some bloom on old wood, others on new so it is important
for you to know what you have and prune accordingly.
When in doubt, do not cut all the way down and protect
stems from freeze and frost.

55. Snowball Hydrangea arborescens
(Soft leaves, round flowers in summer)
For best results, complete renewal pruning every year.

56. #3 PERENNIAL PRUNING
Color is king!

58. WHY IS PERENNIAL PRUNING
IMPORTANT?
*MORE COLOR BOTH IN FLOWERS AND FOLIAGE.
*EFFECTIVE AND ORGANIC INSECT AND DISEASE
CONTROL.
*IMPROVES OVERALL GARDEN APPEARANCE.
*SAVES WORK AND TIME IN THE GARDEN.

59. There are many pruning techniques to enhance perennial
flower performance.
Understanding some of the common terminology may be
helpful.

60. WHAT IS DEADHEADING?
No, it has nothing to do with
Jerry Garcia!
Deadheading is the removal of
spent flowers to prolong bloom,
promote re-bloom , improve
aesthetics or to prevent seeding.

61. Bloom sequencing- Cutting back a plant to delay flowering.
Cutting back- Pruning back foliage and perhaps flower buds
and deadheads to renew a plant’s appearance and/or to
encourage new growth and flowering. Cutting back can also
be used to control eventual plant height and/or flowering
time.
Pinching-Removing the growing tip and first set of leaves to
promote the development of side shoots. Used to promote
fuller, stockier plants perhaps.
Thinning- Removing shoots, leaves or stems to open the
plant canopy allowing for better air circulation

62. PERENNIALS THAT MAY REBLOOM
WITH PROPER PRUNING
Achillea, Aster frikarti ‘Monch’, Astrantia, Campanula,
Coreopsis, Delphinium, Dianthus, Dicentra formosa,
Digitalis, Echinacea, Echinops, Gallardia, Gaura, Geum,
Helenum, Heliopsis, Penstemon, Phlox maculata,
Platycodon, Nepeta, Salvia nemorosa, Scabiosa,
Stokesia, Tradescantia, Viola.
Be sure to select cultivars that readily re-bloom.

63. MAY-JUNE ZENITH OF BLOOM
AUGUST
RE-BLOOM
JULY GETTING TIRED
‘Carradonna’ and
‘May Night’ are better
re-blooming Salvia
varieties.

64. PERENNIALS TO PRUNE FOR IMPROVED
FOLIAGE/OVERALL APPEARANCE
Achillea, Alcea, Alchemilla, Anemone, Arabis, Armeria,
Artemesia, Aruncus, Bergenia, Brunnera, Campanula,
Chrysogonum, Coreopsis, Delphinium, Dianthus, Dicentra,
Echinacea, Echinops, Geranium, Helenum, Heliopsis,
Helleborus, Hemerocallis, Heuchera, Hosta, Iris (bearded),
Kniphofia, Leucanthemum, Monarda, Nepeta, Peony,
Penstemon, Phlox, Physostegia, Polemonium, Pulmonaria,
Salvia, Scabiosa, Stachys, Tradescantia, Veronica, Viola.
When in doubt… if it looks bad cut it off!

65. BEFORE
AFTER

66. DURING
BEFORE
AFTER

68. PERENNIALS TO TRIM FOR HEIGHT
CONTROL/SHAPE/BLOOM SEQUENCING
Achillea, Aconitum, Adenophora, Alcea, Artemesia,
Aster, Boltonia, Echinacea, Eupatorium, Gaura,
Helenum, Helianthemum, Heliopsis, Hibiscus,
Lavender, Lobelia, Lychnis, Monarda, Perovskia,
Phlox, Physostegia, Platycodon, Rudbeckia, Sedum
Autumn Joy, Solidago, Tradescantia, Veronica.
*Trimming may delay flowering.
*Timing greatly affects eventual outcome.

74. Now go outside
and have fun in
the dirt.
Thank you!
16540 CHILLICOTHE RD CHAGRIN FALLS, OH. 44023
440-543-5123 WWW.LOWESGREENHOUSE.COM