110 SWEET PEAS 



Mildew is fairly common on the plants in late autumn, but then does 

 little harm for that season. The Sweet Pea haulm however, should 

 be burnt, for the mildew has a resting stage of existence, and will 

 live in the ground during the winter. To guard against a repetition 

 of the disease in the following year, give the ground a dressing 

 of quicklime in the autumn, and fork it in soon afterwards. 



Blight (Peronospora trifolioruni). This disease is common on 

 many leguminous plants. The first indications of its presence are 

 pale yellow blotches on the leaves, and, in bad cases, on the stems 

 and flower buds. When mature a greyish mould forms. This is the 

 fruiting stage ; the spores then blow about, and infect neighbouring 

 plants. The diseased parts should be removed before this stage is 

 reached, otherwise, the whole row, or clump of plants may soon be 

 ruined. In moist weather the disease is likely to spread rapidly. 

 Badly attacked plants ought to be burnt. In addition to the 

 summer stage of this disease there is the winter, or resting stage. 

 If all the old plants are not burnt, the disease will most probably 

 reappear in spring. As a preventive in addition to removing all 

 the affected parts, those remaining should be sprayed with a prepara- 

 tion made by dissolving 1 oz. of sulphide of potassium and 4 oz. 

 of soft soap in 3 gallons of water. 



Spot (Ascochyta pisi). This disease usually attacks the pods, 

 and occasionally the stems and leaves. Pale spots form on the pods 

 and cause them to be stunted and deformed. As these spots de- 

 velop dark dots form which indicate the fruiting stage. These soon 

 spread to the surrounding plants if the pods are not removed. As 

 it is the practice of many growers to pick all their flowers, and 

 not to let them seed, little harm, if any, can be done by this disease. 

 As recommended in the case of the other diseases all the affected 

 plants should be burnt to assist in stamping it out entirely. Spray- 

 ing with a weak solution of Bordeaux mixture is recommended. 

 This consists of 1^ Ib. of copper sulphate and 1 Ib. of slaked lime to 

 16 gallons of water. Spraying with the solution recommended 

 for Sweet Pea blight is also beneficial. 



