When should a plant be repotted? el 
formation of new spines or a general expansion of the plant body 
with a deepening shade of waxy green. It is easier to transplant or 
repot plants during their growing season; however, there is a danger 
of blighting the flowers unless repotting takes place after the flower- 
ing season. 
Keep a liberal supply of prepared soil on hand, using the basic 
mixture of 14 sand, 1/, loam and 14 leaf mold. To this can be added 
gypsum, charcoal, fertilizer or lime, as indicated for the species to be 
potted. 

Drying out of clay pots may be prevented by 
placing one pot within another (left) or 
plunging the pot in soil or box of sand (right). 
When first potting collected plants or large specimens, especially 
cacti, inspect each plant carefully before potting. If the roots are 
broken, cut them off above the break with a clean, sharp knife and 
dust with powdered charcoal, sulphur, or “‘Semesan”’ to prevent in- 
fection. All damaged and especially fibrous roots should be removed 
just below the plant body. Only one in ten will follow this last in- 
struction because one hates to de-root a plant; but experience will 
eventually prove that a plant will re-establish itself sooner by growing 
a new set of healthy roots. Always trim off diseased roots. 
