BY GLADY JEURINK
directions say “deadhead”. Sounds weird!!! What is it? The
definition is the removal of flowers that have finished blooming. But
why, when, and which plants need this?
deadhead to improve the looks of the plant but may be doing it to
prevent the seed from maturing and then planting themselves in surprise
areas. When plants self
seed, quite often I like the new arrangements they make because many
times it looks better than my original plan.
Some bulbs need
to be deadheaded or the plant will spend its energy producing seed at
the expense of the bulb. I have read that tulip flowers can harbor a fungous so cut
off the flower only to get rid of the disease, but leave the stem which
is still green and making food for the bulb. There are many of the small
bulbs that will reseed and enlarge the size of the bed. For me this has
been my experience with Scilla
Hyacinths. Both of them now come up by the hundreds which
wouldn’t happen if I had deadheaded as soon as the flowers faded. When
you clip Gladiola
be very careful not to remove any more foliage than necessary. It is
busy making food to enlarge the bulb. For years the “rose people”
have been giving specific directions to cut the dead rose
flower back to the nearest 5 leaf that is facing out and the bud on the
cane will produce a new shoot to bloom in six weeks.
Facing out is to keep the center of the rose bush from getting
crowded which encourages fungous disease. Now in the last few years
several people have challenged cutting off so much. A number of people
trying both ways: (a) the old 5 leaf rule and (b) removing just the
spent blossom to see which works best.
before the seeds can mature is for those people that want to control
what plant goes where as well as to keep volunteer numbers down. CLEOME
(Spider Flower), MEXICAN
HATS, GOLDENROD, COSMOS, POPPIES, TALL PHLOX, plus others are well
known for their many seeds. However, if you don’t care then let them
go. The last few years I have a new plant called MEXICAN
HAIR GRASS. It is not hardy here but I have many seedlings as far as
10 feet away from the parent. I
like it very much for stems that blow in the wind. It is about 18 inches
high with thick blond hair. One of my paths is completely loaded with
plants about 2 inches high.
for deadheading is to urge plants to try again. One purpose in the life
of a plant is to preserve the species. Therefore many, but not all
plants will put out new buds after deadheading. Among these are CENTHRANTHUS,
DELPHINIUMS, GLOBE THISTLES, many of the PENSTAMONS,
VERONICAS (Speedwell), TALL
PHLOX, and DIANTHUS. There are others requiring a more drastic action such as
cutting all the way back to rejuvenate the plant. A general rule is (a) if the flower stem is bare cut it all
the way down, or (b) if the stems have leaves then cut just the tired
such as PETUNIAS bloom
heavily for some time before becoming scraggly. But when they do, one
can cut the entire plant back quite severely to survive another blooming
session. Sometimes the packet containing seeds will recommend whether or
not to deadhead. There are some plants that do their own. For example, the very popular newer rose KNOCKOUT. Some plant tags give you instructions about deadheading.
There are a number of people who like to leave seed heads on
during winter either for bird food or winter interest.
related task to deadheading is the one in which shrubs become too wide,
too tall, or just scraggly looking.
If you cut them all the way down there will be a blank space for
one or several years. The
most common method is to go in and remove one third of the stems.
Usually you take out the tallest, or the barest, or the oldest stalks
all the way to the ground. This is best way to prune LILAC, FORSYTHIA, FLOWERING ALMOND, and some other spring blooming
shrubs. This way there is no huge gap and you don’t lose all the
blooms for several years. Repeat this process for the next three years
and then you have a brand new plant.
For LILAC it is good to do this every year.
You can cut the entire shrub or plant way
down at once on some plants, but you lose the bloom for at least two
years and maybe longer. I like to do this in late fall to SPIREA,
BARBERRY, ANNABELLE HYDRANGEA,
and SHRUB DOGWOOD. If you do it any sooner in the year it will stimulate
new growth that will be destroyed by frost. You also need to be careful
which plant you cut when. If the plant or shrub blooms in the spring on
old wood, such as the FORSYTHIA,
and LILAC, it must be done
after flowering. Plants such as CAROPTERIS
(Blue Spirea) and BUTTERFLY BUSH
bloom on new wood so they can be cut down in winter or early spring.
Because of our unpredictable winter, it is generally advised to wait
until spring. I have a WISTERIA in bloom now that I will cut all the way back as soon as it
finishes. I will not have any bloom next year but it branches so wildly
it becomes tangled and the blooms don’t show well. It will be up
within a week and wrapping around its pole tightly.
BUSH) blooms on old wood and any trimming needs to be done
immediately after blooming while Buddleia
davidii (our most common BUTTERFLY
BUSH) blooms on new wood. I generally cut them all the way back
after frost, put a cage around it and fill it with compost in case we
have a nasty winter. The
compost is taken out in spring to spread around the plant as mulch. It
also prevents many weed seeds from starting.