February 2023 - 48

CULTURE REPORT
P:K 1:3 or 1:4) of 20-20-20 or 27-15-12 with microelements.
We also discovered many growers do not often test their
soil, which means they are driving blind. Perform soil tests
throughout the life of the crop to ensure the crop P:K levels
stay in check. In general, growers struggle with too high of
potassium in hellebore crops, which causes the crop to stall
and form less flowers.
The method of watering is very important for hellebores
to avoid stress. Drip irrigation works best, but overhead
irrigation with feed is also possible. With overhead irrigation,
try to avoid watering during the hottest hours of the
day because the leaf temperature is high and the water
temperature much cooler. Leaf temperatures can go up to
105° F, while in most cases the water temperature is around
75° F. This difference creates a temperature shock and
causes stress. Stress will weaken plants and make them
vulnerable to root problems such as Pythium, Rhizoctonia and
Phytophthora. When watering using overhead irrigation on
warm days, irrigate only in the early morning or late evening.
EXPOSURE
Helleborus like cool roots at all times and grow best with
sun protection. It is very important to prevent the sun
from shining directly on the pots at any time. Therefore,
leave as little space between pots as possible and make
sure the leaves cover the pots, creating shade on the pot.
In the summer months, when temperatures are warmer,
take further precaution by using 30 to 35% shade cloth.
If overwintering under plastic, be sure to use a white poly
versus a clear poly. This will help keep plants from burning
on sunny days.
TEMPERATURE
In the fall, the perfect temperature for growing hellebores
is between 40 to 50° F; this range triggers the flowers to
HELLEBORE FROSTKISS AND WINTER ANGELS SERIES SPECS
USDA Zones
5 to 8
Liner Size
Source
Liner Availability
Varieties Offered
Suggested Finish
Size(s)
Average Finish
Times
48
72-cell and 32-cell
Tissue culture
Spring: 72-cell; Fall: 32-cell
13 in a range of colors including red,
pink, green, white and bicolor
2.5 quart to 1 gallon
40 to 52 weeks using 72-cell and 18 to
26 weeks using 32-cell for 1 gallon
FEBRUARY 2023 GPNMAG.COM
initiate. Depending on the climate this will occur between
September and December. In winter, keep the Helleborus
inside a frost-free structure with temperatures ranging
between 32 to 40° F. When there is no frost, the plants
will flower by their natural genetics; if there is frost, it will
postpone the flowering time. In the summer months, it is
important to shade at 30 to 35% when temperatures rise
above 80° F.
INSECTS & DISEASES
Hellebores are tough plants and rarely get diseases. The
main disease issue seen is Botrytis in the flowers and it can
also show up in the stems close to the soil line. Prevent this
by keeping plants dry and in an area with good airflow.
Watch for aphids as they transmit virus, also spider mites
can be an issue in drier climates. In wet conditions, snails
can be problematic. Discourage snail infestations by keeping
the crop drier and choose a welldrained
location to set the crop
down on.
Hellebore leaves
are the lungs of
WHAT SHOULD YOU
NEVER DO TO A
HELLEBORE?
the plant - they
provide the energy
needed to build
flower buds.
Put the clipper down.
Hellebores should
never be pinched; as
Bart would say, the
leaves are the lungs of
a hellebore. Every leaf on
a hellebore helps to form
flower buds, so removing leaves
will decrease flower count and
overall finished quality. I know the urge
to pinch the damaged leaves is high, but let those leaves
continue to bring energy the hellebore needs to form
flower buds. Once the plants are ready to ship and flowers
are budded, a few damaged leaves can be removed.
Never apply a growth regulator as hellebores are slow
growing. PGRs can slow a hellebore down for months and
can delay or even stop flowering altogether.
Every situation can be different with so many climates,
different growing operations and other variables here in
the U.S. We are here to help customize a hellebore program
for your operation. Please do not hesitate to contact us at
PP&L with any questions; we can put you in touch with
Bart or even set up a visit to see your crop so we can help
you grow the best hellebore Frostkiss and Winter Angels
crop possible.
April Herring-Murray is marketing director at Pacific
Plug & Liner. She can be reached at aprilh@ppandl.net.
http://www.GPNMAG.COM
February 2023

Table of Contents for the Digital Edition of February 2023
