6 MASS. EXPERIMENT STATION BULLETIN 225. 



iiiiiiaired to tlie extent tliat they cannot mature tlieir fruit and grow new 

 foliage as normally growing plants can and consequently the fruit is pre- 

 maturely ripened. As cucumber jilants grow older, especially with the 

 string method, the\ shade each othei- more, and for that reason the lower 

 lea\es either drop oft naturally or suc'cumh to disease. Lender such con- 

 ditions the plants are unable to carry to maturity the fruit which was pol- 

 linated when they were in a fairly healthy condition, and conse(]uently 

 many yellow pickles appear. 



Soil Conditions and Yki.i.ow Pickle 



Ordinarily the soil in a greenhouse is so well manured^ that if it is 

 h.andled i)roperly there will be suft"icient soil nutrients present to carry a 

 crop of cucumliers from nine months to a year, or as long as the vines 

 are able to produce a paying crop. There are, however, certain conditions 

 caused by poor drainage which tend to shorten the growing jieriod of a 

 plant, and materially cut down the yield. After cucumbers are trans- 

 planted, a period of soil saturatit)n with water follows so that the plants 

 are continually growing in a wet soil, which is usually too wet for healthy 

 growth. If good drainage is provided, as in benches, little damage will 

 result. If no drainage is i)r()vided, the soil becomes water-logged, 

 oxygen is excluded and practicallx no nitrilication takes place. The plant 

 does not receive sufficient nitrates to make a healthy growth and a large 

 number of yellow pickles results. Even if compost manure or fertilizer 

 is applied on the top of the ground and kept moist, the j^lant will not 

 function jiroperly as long as the soil is in a water-logged condition. This 

 undoubtedly has mucli to do with the longer growing period of cucumbers 

 when grown in benches. 



The cucumber plant needs a large (luantity of water, but it will not 

 thrive if the roots do not receive suft'icient air in the presence of too much 

 water in the soil. Greenhouse growers claim that plants wilt if the soil 

 is not thoroughly wet down. This is true, but they will wilt even though 

 more than the necessary amount of water is added, the reason being that 

 the plants have received so much water from the time they were set in the 

 beds that the root system is not large enough to balance the upper part 

 of the plant. The roots remain near the surface and will not branch out 

 and down for water and food. They are near the surface where there 

 is air. It is the same condition found in a i)oorly drained field. If plants 

 wilt during hot dry weather, growth is interruiited to the extent that many 

 cucumbers become stunted and produce either nubbins or yellow pickles. 

 Proper watering after transplanting will prevent much of this trouble. 

 An excess of water from the time the seed gei-minates makes a soft plant 

 \\ Inch recpiires a large amount of water. It is imjiossible to give such a 

 jilant sufficient water during hot dr\ weather to i>re\ent it from wilting, be- 

 caiLse the root system is not large enough to replace the water that is 

 given off by the leaves. L^ndoubtedly, cucumbers grown with less water 

 from the start are more lignified (less soft), ha\e stiffer cell walls, and 

 do not (Iroo)) as readily even when there is a slight water deficit. 



This condition of the soil has considerable influence on the health of 

 the plant. The number of yellow i)ickles will be influenced by the con- 

 dition of the plant. 



