Four Star Culture Guide - 2019 - 102

GRASSES
Perennial

ZONE HARDINESS
4 - 9 Karl Foerster and 'Overdam' Calamagrostis
5 - 9 Ogon Acorus, Graceful Grasses® Blue Mohawk® and
Spiralis Juncus

liners into a Trade or True gallon is desired on slower growing
perennial grasses such as Acorus, it's best to do a summer
planting and plan on an entire growing season for proper
bulking and vernalization for sales the following spring.

NUTRITION
pH: 5.8 - 6.5
EC: (2:1 extraction method) 0.9 - 1.5
Moderate fertilization is recommended. 100ppm - 200ppm N

VERNALIZATION
No vernalization should be needed because perennial grasses
are not normally grown for flowers. Calamagrostis is the one
exception, and they are sold with the appropriate amount of
vernalization for spring flowering.

TEMPERATURE for forcing from a liner
Forcing/Growing on: 60 F Night - 65 F Day
Holding: 40 F Night - 50 F Day
Plants can be moved outside once the crop has reached a
saleable size and the danger of frost has passed. An open
environment will often strengthen the stems and produce a
better finished product.
WATERING
Grow plants on the dry side during the start of forcing to
encourage root development and discourage root rot, but do
not allow plants to wilt. Keep the soil evenly moist. Ogon, Blue
Mohawk and Spiralis are water or bog plants and enjoy a moist to
wet growing condition.
TIMING
Supernova® 28 Liner (if applicable) to Trade Gallon/True
Gallon: 8 - 12 weeks with one plug per container. A typical
planting date for spring forcing would be Week 8 for finishing
in Week 18. Forcing 1 gallon containers in the spring from liners
doesn't produce as high of a quality finished product as does
the typical summer/fall bulk and vernalization model.
50/104 Liner to Quart: For spring growing, allow 8 - 10
weeks with one plug per container. A typical planting date
for spring forcing would be Week 10 for finishing in Week 18.
Forcing quarts in the spring from liners doesn't produce as high
of a quality finished product as does the typical summer bulk
and vernalization model. Additionally, if finishing Standard 50

PLANTING
Liners should always be planted even to the soil line of the plug.
Calamagrostis is shipped semi-dormant and may appear to be
dead at the time of arrival. Hold these liners in a cold house
until it's time to plant: 35 F - 44 F degrees for this is adequate.
Letting most of these perennial grasses sit out on warm
greenhouse benches for a prolonged period of time can allow
them to start to break dormancy and can later adversely affect
the finished look of the product.
When growing perennial grasses, we recommend using an
aged or composted pine bark-based media, as opposed to
annual growing mixes that traditionally tend to be heavier
in peat. Bark adds weight and stability to the growing mix
and tends not to compress and shrink over time, thus adding
the longevity that can be needed on long-term crops such as
perennials. If you're planning to grow and sell these in a very
short amount of time, this is less of an issue. It is also less of
an issue with the water grasses such as Acorus and Juncus, as
these enjoy more of a moist growing condition. A peat-based
media can assist in providing that.
LIGHT/LIGHTING
During forcing, plants should be given as much light as possible.
Plants should be spaced such that they do not shade each other.
However, shading of Acorus in the brighter, warmer summer
months is beneficial in keeping the nice gold coloration.

Four Star Greenhouse I www.pwfourstar.com I 734-654-6420
102

The rates and chemicals listed are based on our southeast Michigan growing conditions, and are not recommended for nationwide application.
Please adjust the rates and spray applications to your location and facility.

http://www.pwfourstar.com

Four Star Culture Guide - 2019

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