sarm 
AN ENCYCLOPAEDIA 
OF HORTICULTURE. 231 
Cactus—continued. 
absolutely necessary to ensure perfect drainage; a good 
“ stopper” should, therefore, be placed over the hole at the 
bottom of the pot, and about one-third of its depth filled 
with draining material. The best time for potting is during 
February and March. Turn out the plants, and remove 
nearly all the old soil from the roots, taking away any dead 
aiid 
1. Opuntia, 5. Mammillaria. 
2. Cereus, 
5. Opuntia streptacantha. 
4. Cereus candicans. 
7. Echinocereus electracanthus. 
8. Mammillaria. 
6. Cereus peruvianus monstrosus. 
+ 
Cactus—continued. 
vessels. A good top-dressing, with an occasional dose of 
weak liquid manure, is all they will require for several 
seasons. 
Watering. This must be discriminately managed, espe- 
cially during the winter; for, whatever their treatment 
as regards temperature during that season, they must be 
9. Echinopsis formosa. 
10. Echinocactus Visnaga. 
11. Cereus peruvianus var. 
12. Opuntia candelabriformis, 
13. Cereus strictus. 
14, Pilocereus senilis. 
15. Cereus Tweedii. 
16. Cereus chilensis. 
Fic. 312. GROUP OF CACTI. 
or decaying roots which may be observable. Place some of 
the roughest soil next the crocks, and gradually fill the pots 
with the finer material, well working the same amongst the 
roots; finally press the soil moderately firm. Do not water 
for a few days after potting, but syringe every evening, 
especially if the weather be fine; a little extra heat may 
be given after potting, to excite new, healthy growth. It 
will not be necessary every year to repot specimens in large 
studiously watered, and anything like a saturated condi- 
tion of the soil should be avoided. If the temperature is 
brisk, a little water may be given once a week, or perhaps 
not quite so often. If the plants are subjected to very 
cool treatment, water must be sparingly administered 
during November, December, and January; after which, 
they should be examined weekly, and very carefully at- 
tended to. During the summer months, when in active 
