22 
BULLETIN 57, HAWAII EXPERIMENT STATION 
DEPTH OF PLANTING 
The rootstocks of the edible canna are inclined to grow at or 
above the surface of the ground. (Fig. 13.) Many of them in a field 
12 months old will be found growing several inches above the surface 
with no root system whatever. Such rootstocks usually are stunted. 
This tendency might be overcome by planting in furrows. Hilling- 
in gradually might further aid by raising the ground to a level with 
the ascending rootstock growth. An experiment was begun on a 
number of 0.1 -acre plats to determine the effect on germination and 
yield of planting edible canna rootstocks at different depths, varying 
from 8 inches below the surface to the top of an upraised bed. Mill- 
run seed — that is, any type of seed with a visible bud — was planted 
Fig. 13.— Base of a canna hill 22 months old. Note the tendency of the rootstocks to grow above 
ground 
at intervals of 4 by 4 feet, and the resulting crop wa,s harvested at 
20 months. Table 9 gives the result of the experiment. 
Table 9. — Effect of depth of planting on germination and yield of edible 
canna 
Plat 
No. 
Manner of planting 
Propor- 
tion of 
rootstocks 
failing to 
germinate 
Gross 
yield of 
rootstocks 
per acre 
Net 
yield of 
rootstocks 
per acre 
Average 
weight 
per root- 
stock 
20 
Hilled in gradually in 12-inch furrows 
Per cent 
12.7 
8.8 
14.2 
11.1 
16.2 
Tons 
38.0 
37.9 
30.3 
37.5 
35.9 
Tons 
34.1 
34.0 
27.2 
33.6 
32.2 
Pound 
0.74 
21 
Planted in 12-inch furrows (not hilled in) 
.67 
?,?, 
Planted in an upraised bed 
.59 
?3 
Level culture; seed 8 inches deep 
.71 
?4 
Level culture; seed 1 inch deep 
.68 
Little difference in yield or average weight per rootstock was ob- 
served in the plats, except in the upraised bed which was decidedly 
inferior in both respects. Plat No. 20, in which the seed was planted 
