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Gardening for Amateurs 



lime contains much water, consequently a 

 greater quantity is required, i.e. a pound 

 of slaked lime does not contain as much 

 " lime " as a pound of quicklime. Acety- 

 lene gas residue may be treated as an impure 

 slaked lime after exposure to the air for a 

 week. Gas lime is the cheapest and most 

 profitable kind of lime ; fresh from the 

 retorts it is highly charged with poisonous 

 impurities, but after being turned over three 

 times at weekly intervals it may then be 

 regarded as impure slaked lime. To utilise 

 its insecticidal properties spread it on the 

 soil when obtained, leave it for a day or 

 two, then dig it into the soil. This should 

 be done in autumn, and by spring all the 

 soil poisons will have been dissipated. 



Gypsum (sulphate of lime). This mate- 

 rial is like plaster-of-Paris, and is a neutral 

 form of lime combined with sulphur. It is 

 not required where superphosphate or dis- 

 solved bones are being employed, as these 

 always contain sulphate of lime. It can 

 be dressed on land at all times of the year, 

 and will be found excellent for root crops 

 like the Turnip which require lime and 

 sulphur. It absorbs ammonia, and is there- 

 fore invaluable for mixing with farmyard 

 manure or the urine from stables, to pre- 

 vent waste of any of the nitrogen com- 

 pounds ; if worked into soils the gypsum 

 would then yield up its ammonia to vege- 

 tation. Lime in this neutral form may be 

 applied to the garden with the organic 

 manure. 



Limestone is applied to soil in some 

 districts ; it is a harmless form of lime, 

 slow in acting, yet useful for counteracting 

 any sourness. Pot plants should scarcely 



ever have lime added in any other form ; 

 old mortar, plaster, or well-weathered lime 

 is simply the carbonate, with harmless 

 impurities, and in this form it will not 

 injure the most delicate plants. 



Ground Shells. When the plant will 

 not be repotted for a long time, nor the 

 compost renewed, ground shells are the 

 best form in which to add lime to the soil, 

 and the lasting effect will continue for 

 years. 



Crops which Benefit. Almost without 

 exception all crops benefit from lime. 

 Cabbages, Cauliflowers, Turnips, and all the 

 members of the Pea and Bean family of 

 plants require soil containing much of 

 this substance. Potatoes, however, derive 

 no benefits from lime in any form, and the 

 Potato soil should seldom be limed ; in 

 some cases lime causes a diminution of 

 the Potato crop. If the soil was dressed 

 with lime in a previous year the plants 

 will not be affected, because by that time 

 the substance will have passed into the 

 soil in the comparatively harmless form of 

 carbonate. 



Lime checks many diseases, such as 

 " finger and toe," or club root ; but, on the 

 other hand, it favours the development of 

 a few, the commonest being Potato scab. 



Testing for Lime. Fertile soil should 

 contain from 2 to 7 per cent, of lime. To 

 ascertain if lime is present in soil, place 

 some in a tumbler, add water to make a 

 cream, and stir until all air bubbles have 

 disappeared. Now add a little hydrochloric 

 or muriatic acid, and if lime is present 

 effervescence will immediately be noticed. 



Amounts to apply (maxima) : 



FORM 



QUANTITY 



REMARKS 



