Handbook of Plant and Crop Physiology

66 CHONG ET AL.

TABLE 2

List of Selected Flowering Herbaceous Plants Showing Desired Medium Temperature Regimes for the Germinating and Posttransplant

Stages and the

Approximate Time for Germination under Greenhouse Conditions as well as the Need for Light or Seed Pretreatment

Medium temperature (

C)

Plant

Posttransplant

Days to

Light or

Species

type

Germination

(night)

germinate

dark

Pretreatment

Remarks

Definitions of plant typeA

Annual. A plant that normally complete its life cycle within one calendaryear. Some may be considered short-lived perennials in areas of mild wintersor with adequate protection (i.e., snow cover, mulch, sheltered location).

B

Biennial.

A plant that require 2 years to complete its life cycle, usually pro-

ducing vegetative growth only in the first, then flowering and dying in thesecond.

P

Hardy herbaceous perennial.

A plant that lives longer than 2 years, normally

producing flowers and seeds each year.

Sow, then freeze 3

wk

Stratify 21

C 3 wk,

freeze 5 wk, thensow

Sow, then freeze 3

wk

None

(^21) 7–105–8 30 30
14–21
30
10–14
Acanthus spinosus
Bear’s breechesAcanthaceae
Achillea filipendulinaA. millefolium
YarrowAsteraceae
Aconitum
spp.
MonkshoodRanunculaceae
Actaea alba
BaneberryRanunculaceae
Adenophora confusa
Lady bellsCampanulaceae
Adonis
spp.
AdonisRanunculaceae
Agastache foeniculum
P P
P-W
P
P-W
P P P
10–12 20–24
18
12–15 5–10 21–23 12–15 21–24
1510 10
10–15
LL D D L D
D or L
Use fresh seed.Lower germinating medium
night temp. by 3
C.
See note 6.Seeds may produce inferior
plants; vegetativepropagation may be morereliable.
Fresh seed will germinate
much more quickly thanolder, ripened seed.
Drying of seed will delay
germination.
HHP


Half-hardy perennial.
A plant that may survive mild winters or harsher
winters with adequate protection, i.e., snow cover, mulch, sheltered loca-tion.
P-W


Perennial wildflower. A plant that is indigenous to North America or hasbecome naturalized to the point of being considered so.