Handbook of Plant and Crop Physiology

GERMINATION AND EMERGENCE 85

Sow at 21

, allow

roots to emergethen refrigerate3–5

C 8–10 wk

Soak in H

SO 2

(^44)
min, may induceuniformgermination
Stratify 5
C 2 wk
10–1410–21 7–10 30–60 12–1612–16 5–18 7–147–14 7–12 4–10
10
25–30
Oenothera argillicolaO. missouriensis
Evening primroseOnagraceae
Osteospermum
spp.
Star of the VeldtAsteraceae
Paeonia
spp.
PeonyPaeoniaceae
Papaver rhoeasP. orientalis
PoppyPapaveraceae
Pelargonium
hortorum
GeraniumGeraniaceae
Penstemon gloxinioidesP. strictus
Penstemon, beard tongueScrophulariceae
Petunia
hybrida
PetuniaSolanaceae
Phacelia campanularia
California bluebellHydrophyllaceae
Phlox drummondiP. paniculata
PhloxPolemoniaceae
P-WP-W A
P AA A A
P-W A A A
P
18–2120–24 20–24
22
20–2420–24 21–24
1616
21–24 12–15 15–16
21
13–1618–21 7–10
(^20) 7–107–10
16–18
1010
13–16 12–15 10–13
D or L
L
D or L
DL
D or L
L L L DD
Reduce night temp. of
medium by 3
C for best
germination.
Vegetative propagation is
preferred because it takes5–7 years to produce aflowering plant from seed.
Reduce night temp. of
medium by 3°C for bestgermination.
Presow drench medium with
fungicide to prevent damp-off.
Keep surface of medium
constantly moist untilgermination is complete.Seedling vigor varieswidely between cultivars.
Presow drench medium with
fungicide to preventdamping off.
continues