Oct. 1, 1901.] THE TROPICAL AGRICULTURIST. 
229 
the discs set at a slight angle, the manure was then 
spread along this drill by hand, the machlDe again ran 
over the hill with the;discs;set at a greater angle which 
hilled it up to a good height and covered the manure, 
and the land is then ready for planting the cuttings or 
slips. 
PLANTING, 
The slips should be planted in rows about 18 
inches apart, an i with the rows 3 feet 6 inches apart 
it will take 8.556 to the acre. If the rows are 4 
feet apart 6,136 to the acre. The best method 
for planting is for oue roan to go along the row 
with a marker and mark out where the slip is to 
go and to make a hole in tbe ground, the planter 
following and putting the slip in the hole pre- 
viously made, care being taken to press the earth 
well round the slip. If planted on a dull day and 
the ground is fairly moist the percentage of misses 
will be very small. Any slips that fail to take root 
can be replaced later on. Later in the season if 
it is deiirable to put out a larger area, or a large number 
of misses require to be replaced, slips can be cut from 
any of the growing vines and planted out in exactly 
the same manner as those taken from the seed 
laed as previously described. From observations 
made by the writer it does not appear to have my 
effect on the crop whether the slips are taken 
from large or small tubers, so long as they are 
healthy and vigorous. It would therefore be more 
profitable to use the smaller size potatoes for this 
purpose, which are not so ready of sale as the larger 
ones. 
CULTIVATION. 
When the young plants are once established very 
little more requires to be done, except to run the 
Planet Junr. cultivator between the rows at fre- 
quent intervals so as to keep the ground free from 
weeds and well stirred. If there are many weeds 
come up, it will be advisable to give the hills a 
good hoeing to prevent the weeds from growing and 
depriviug the potatoes of their food and moisture. 
In runuing the cultivator between the hills care 
must be taken not to set the implement too wide 
so as to tear down the side of the hills and expose 
the young roots to the sun. 
HARVESTING. 
This operation must be performed by hand, as the 
tubers prow to a large size, and if dug by a plough 
large numbers are cut to pieces, and otherwise 
damaged. They should be dug during dry weather 
and as soon as the tubers have reached maturity and 
before they have time to make a second growth. The 
maturity of the sweet potato may be ascertained by 
breaking it. If the sap oozes freely it is of course im- 
mature, if little sap exudes it is nearly mature- Ex. 
perience will soon be gained in this matter. As a rule 
the tubers are ready to dig about the end of March or 
the beginning of April. Care must be taken in dig- 
ging and handling not to braise the potatoes, as a 
small bruise when freshly dug is likely to cause the 
potato to rot. It is also beneficial to leave the potato 
in the ann for a short time after being dug before 
bagging or putting into a shed, and when bagging 
all damaged, out or bruised pouatoes must be excluded. 
These damaged potatoes will only keep for a short, 
time, and can be used on the firm for feeding pigs or 
Other stock 
PRESERVATION. 
One of the most difficult points about Sweet 
Potato growing is difficulty of keeping them so as to 
maiket at times of the year when they will fetch a good 
price, and also during the winter months so as to 
have a supply for the seed beds in the spring. The 
best way on a large scale is the method of '' hilling 
or banking." This should be oaraed out under a 
shed or open roof so that the bank is not exposed to 
the weather. The best method to proceed is — lay on 
he ground, which must be dry, a good layer of 
K^w ; on top oi (bia pac^ the potatoes ia tha fQroi 
of a mound and cover the whole heap with a quantity 
of straw, and then put sufficient earth on top to 
cover the whole, In many instances where large 
stacks are built a ziuc pipe perforated with 1 inch 
holes IS placed through the centre of the stack 
which allows all surplus moisture to escape while 
the potatoes are going through the sweating process. 
Another method which is only applicable on a smaller 
scale, but which I have always found very success- 
ful, is to obtaiu a number of old empty cement 
barrels, which can generally be picked up very cheap, 
place in the bottom of the barrel a layer of dry- 
sand about 3 inches deep, then a layer of potatoes 
then another layer of sand and so on until full' 
placing about 4 inches of sand on top of the barrel ■ 
this will keep the tubers quite sound all through 
the winter, and only one barrel need be opened 
at a time as required for use. 
VARIETIES 
There are a large number of varieties of swee 
potatoes. At the Georgia Experimental Station, 
U.S.A., thirty-four varieties were grown last season 
and reported on, the heaviest yield being the White 
St. Domingo. In the Australian States, however 
only two varieties are at the present time obtainable, 
and they are generally known as the White Svfeet 
Potato and the Eed Sweet Potato. Both are good 
varieties and grow and yield well ; the white will grow 
in cooler districts than the red. 
DISEASES. 
The Sweet Potato is attacked by several fungui 
diseases. The most important of these is the Black 
Eot Fungus Ceratocystis Fimbnata. The accompany- 
ing illustrations show a tuber attacked by this 
disease. It attacks the plant at any time of its exist- 
ence even after being stored. The black spot is at 
first very small, gradually increasing in size unti 
the whole tuber is destroyed. Owing to the nature 
of this disease, it is important that every precaution 
should be used to prevent it obtaining a footing. For 
this reason no diseased tubers should be used in 
obtaining shoots, young plants should be selected 
with great caution and diseased or suspicious tubers 
destroyed. Should any signs of the disease appear 
the plant should be immediately sprayed with itor- 
deaux mixture, which will prevent the development 
of the spores. All diseased plants should be burned, 
so that 1 he spores of the disease do not remain iu the 
soil. Do not plant in the same ground as a previons 
erop has been in, but carry out a system of rotation 
of crops and thereby prevent the spread of disease 
Journal of the Department of Agriculture of Western 
Australia. 
^ 
PLANTING AND NEW PRODUCTS IN 
ZANZIBAR. 
COFFEE-TEA-CACAO— RUBBER AS WELL 
AS COCONUTS AND CLOVES. 
Only in April 1901 does the report dated February 
24th, 1900, ot Mr, R. N. Lyne, Director of Agriculture, 
reaches us : — 
He says : — Mr. W. J. Eobertson (who must be an 
cold Ueylon planter) has briefly explained the pro- 
gress that has been made at Dunf^a with Colfeej 
Tea and Cocoa. Vou will observe that in each case 
the condition of the young plantation is satisfactory 
and the prospects encourugmg. Mr. H. Listher'j 
report on the Tundaua plantation is included. This 
haSj^been a very bad year for cloves, coconuts and 
fruit, and the natives at oue time suffered much froni 
the failure of their first crops. Growih has, however, 
revived under the timely rains of December and 
January. 
(b""rom Mr,^ W, Ji liobertson's Eeport ou Ne^y 
Products.) 
