THE NATIONAL NURSERYMAN 
399 
PROPAGATION OF HERBACEOUS PERENNIALS 
SEED SOWING 
By WILLIAM LAMB 
This group of plants is so large and varied that it would 
be impossible to give fixed rules and methods that would 
apply equally well to them all, at the same time they do fall 
into groups by which they may be considered intelligently 
and to which general principles may be applied. 
A thorough plantsman can usually tell by the look of a 
plant if it is possible to propagate it from cuttings, or if it will 
be necessary to layer, bud, graft or by division, or if it will 
come true from seed. 
Propagation by seed is the most natural method and a 
great majority of Herbaceous Perennials may be propagated 
in this manner. 
There is a decided advantage in having a greenhouse that 
can be used for propagating perennials, operations can be 
started in January, and in the case of certain cuttings, early 
in December. 
The greenhouse requires no special construction, so long as 
it is light and the temperature can be kept to about 55 degrees 
at night in cold weather. 
Seed boxes should be made three inches deep and a unifomi 
size to fill the entire space on the bench, so no room may be 
wasted. If for any reason the seed boxes must be shifted or 
the seedlings become large enough to prick off, the boxes can 
be readily closed up or others set in their places. When 
making boxes always allow for drainage by leaving cracks 
between the boards or bore holes in them. 
When preparing the seed boxes put a layer of rocks in the 
bottom, then about one inch of well rotted manure after 
which fill with screened soil, level with the top of the box. 
Use the fingers to press the soil down firm and even, the 
center will be found firm enough, work the soil toward the 
comers when it is loose. When ready for sowing the seed, 
the surface of the soil should be level and about one-half inch 
below the top edge of the box. 
Judgment must be used as to how thick seed should be 
sown. Large seed, such as Lupinus polyphyllus, require 
more space than small seed like Heuchera sanguinea. 
A box 16 inches by 19 inches will produce three or four 
hundred Lathyrus latifolius, while the same box would grow 
almost as many thousand Campanula carpatica seedlings 
ready for pricking off or transplanting. 
After sowing the seed, press it into the soil with a small 
piece of smooth board then all the seed will be about the 
same depth and if covered evenly with fine screened soil, 
most of the little seedlings will break through the ground at 
the same time. 
Wooly or winged seed, such as Anemone Pulsatilla, 
Gaillardia, Echinops, etc., can not be pressed into the soil 
like Aquilegia, Campanula, Lychnis and other hard seed and 
require more soil for covering. 
When sowing seed outside, a good rule to follow is to 
cover the seed with soil, a depth equal to the thickness of the 
seed. This is not necessary inside, especially if the seed be 
pressed down evenly with a board; harm can only come from 
watering improperly. 
A thorough watering should be given with a can and fine 
rose, after sowing the seed and the box has been set on the 
bench or in the place where it is going to remain while the 
seed is germinating. Never handle a box of seed just after 
watering, as a crust is sure to form on top of the soil. Noth¬ 
ing else but a can and fine rose should ever be used when 
watering seed boxes or small seedlings. 
Shade the seed boxes with paper until the seedlings begin 
to break through the soil. The shade keeps the soil moist, 
helps to prevent the covering of soil forming a crust on top 
of the seedlings, and seed will germinate more quickly in the 
dark. 
The shade must be removed when the seedlings begin to 
break through the soil or they will grow lanky and damp off. 
Begin in January by sowing seed that will germinate 
quickly, such as Beilis perennis, Myosotis palustris, Alyssum 
saxatile, etc., follow every couple of days by sowing a few 
more boxes of seed, so they will not all be ready for pricking 
off about the same time. This work can then be taken care 
of without extra help until work begins outside, about the 
first of March. 
While it requires two or three weeks for seed to germinate 
in January, one or two weeks is sufficient time to germinate 
the same seed in the latter part of February and March. 
It is best to sow seed of new plants and very small quanti¬ 
ties of seed about the first of March, for the largest percentage 
of seed to germinate. I have found a great many kinds of 
seed will produce the greatest percentage of seedlings if sown 
outside a couple weeks after it has ripened on the 
plants. 
Always allow for two or three sowings of the same kind of 
seed. Sow about one-third of the packet of seed at the first 
sowing, in case of failure through dull weather or other 
causes, enough will be left to try again, when the weather is 
more favorable. There are more clear days as spring 
approaches and the sun gives more heat each day. 
The temperature should not go below 55 degrees at night 
and 65 degrees in the day. The ventilators should be 
opened every day, if only for a short time, no matter how cold 
it may be outside. This will help to prevent the young 
seedlings from damping off, especially in January and 
Februarv when there are so many dull days. It freshens the 
inside atmosphere and helps to keep down a large family of 
Aphis. 
The seedlings will grow so thick at times as to raise the soil 
in a crust, instead of pushing through it. This crust is 
formed of the fine soil used when covering the seed at the time 
of sowing. This crust must be taken off to save the seedlings; 
if it will not wash down between the little plants after water- 
