Overcrowding 



Overcrowding, too close planting or seed-sowing, 

 standing plants too far from the glass, allowing their 

 more vigorous neighbours to overshadow them, 

 shading them and forgetting to remove the shade, 

 are all common ways of causing etiolation. The 

 checking of food-making in such plants need not 

 again be referred to, but it may be worth while to 

 point out the especial danger of permitting the 

 condition to overtake yoimg seedlings which have 

 only the slender store of food laid up for them in the 

 seed to fall back upon. They may be completely 

 ruined by it, and in any case their delicate tissues 

 wiU be laid open to attack by damping-o£E fungi. 



Etiolation may also be induced in greenhouses 

 by keeping the temperature too high in winter and 

 urging growth when the light is naturally dim and 

 of but short duration. It is a wise rule that delays 

 seed-sowing until the " turn of the year " when the 

 light begins to increase. Etiolated growth is almost, 

 and sometimes quite, useless to the plant ; it may be 

 an actual expense, and is always a menace, as it more 

 readily succumbs to adversity. It is desirable in 

 some garden plants which are blanched before use, 

 but must only be induced in these after they have 

 been grown under conditions which have ensured 

 the storage of ample food to supply the etiolated 

 growth. 



Even when Ught is sufficient, foliage formed in 

 a moist atmosphere by plants well supplied with soil 



36 



