Deeper planting bulbs
DaveKarn@aol.com (Mon, 17 Nov 2003 12:08:55 PST)
In a message dated 16-Nov-03 4:41:53 PM Pacific Standard Time,
brian.whyer@which.net writes:
. . . planting bulbs deeper than "normal" discouraged bulbs from increasing
by side bulblets, and consequently gave larger flowers and continuing
flowering in subsequent
years. In this case large flowered tulip hybrids were the example. The
commentary I think said "deeper planting, equals cooler bulbs, larger flowers,
longer bulb life," though presumably less bulb increase. Is this "cooler bulbs
point" a valid argument for bulbs like tulips, or indeed bulbs in general?
e.g. some reticulate irises which split up much
more readily than tulips in my experience.
Hello all ~
In the commercial growing of daffodils ( Narcissus ), primarily the 4n
hybrids, a "rule of thumb" is that shallower planting can contribute to more rapid
increase. In a business based on the selling of dry bulbs, this can be an
important consideration! On the other hand, planting a daffodil somewhat deeper (
5-7" of soil over the tip of the bulb ) than would be considered normal (
2-4" of soil over the tip of the bulb ) does, indeed, contribute to a slowed rate
of multiplication. The reason is simple. It takes more energy to grow from
a depth than it does to just poke above the surface to reach the light. With
less total energy available, multiplication ( a function of stored energy ) is
retarded. In this case, it's an important consideration when planting
daffodils in the landscape where the intention is to keep them for a longer time
before being forced to dig and separate them to improve flowering that tapers off
as the bulbs increase and become crowded.
Tunicate bulbs ( generally ) produce an unbranched mass of roots from the
basal plate -- an important consideration to bear in mind. To insure long term
success in landscape plantings, one has to loosen the soil to a depth of at
least 18" to accommodate this trait. It is also helpful to work in some moderate
analysis fertilizer at that depth some time before planting begins. Also,
tunicate bulbs appreciate substantial moisture during their period of growth.
Daffodils can handle at least an inch of water per week -- assuming the soil is
friable enough for the excess to drain away. They also respond better when
kept dryish during Summer dormancy.
I would agree with the suggestions that have been made with respect to
planting depth for seed of this type ( round, hard, black seed ). I generally plant
my daffodil seed at least an inch to an inch and a half deep in the
indigenous soil in full sun and find this works just fine. Although I've not always
been able to follow the advice about planting the seed as soon as it is falls
from the capsule, it is probably wise to do so. When fresh, the seed is plump
and shiny black. As it dries in preparation for dormancy, it shrinks and
becomes matte black. The dormancy inhibitors formed during this process have to be
washed away by rainfall before the seed will sprout. In other words, planted
fresh in June in this climate one will often see the little spears of growth
in late Fall. Planted in Spring ( seed harvested the previous June ), the
seed will not germinate until the following Spring. I know -- been there, done
that!
Best,
Dave Karnstedt
Cascade Daffodils
Silverton, Oregon USA 97281-0237
Cool Mediterranean climate -- wet Winters, hot and dry Summers; USDA Zone 7-8
.