470 Hints on Potato Culture. 



Akt. VI. Hints on Potato Culture. By John Robertson, F.H.S, 



I AM persuaded that a great proportion of the failures in 

 potato crops, so much complained of, proceeds from the careless 

 or injudicious treatment of the potatoes intended for seed or 

 sets, or from late planting. If' stored in houses during the 

 winter, the potato sets will lose much of their succulency and 

 sap, or will vegetate prematurely ; from which, at the season of 

 planting, they will be found to be, in a great degree, exhausted 

 of that saccharine pabulum which was stored up in their tubers 

 for the nutrition of the young shoots; and the germ, conse- 

 quently, pushes feebly, or decays before it can establish fibres 

 for its support. Seed potatoes should, at the period of getting 

 up, be selected of the best ; and, to preserve them fresh and in 

 vigour, should be kept, during the winter, mixed with a little 

 earth, in narrow and shallow pits, well protected, and in a dry 

 situation, until the period of their vegetation ; and then, to 

 retard it, they should be removed into cool sheds or out-houses 

 till the season for planting, which should not be deferred later 

 than April, or as much earlier as the order of their growth 

 requires. An occasional change of seed for some of a different 

 soil is necessary ; as, when the same stock is used in the same 

 ground for several successive seasons, it degenerates in quality 

 and produce; and I have found the produce of a new stock, 

 from fresh ground, exceed that of my own full one third, under 

 similar circumstances ; and, though the latter was well chosen, 

 and apparently superior, it even was above ground ten or twelve 

 days before it. Repeated successive croppings of the same ground 

 with potatoes produce a similar effect. When potatoes are 

 planted in drills, about 2^ ft. asunder, I have found from 9 in. to 

 1 2 in. the best distance to place the sets apart ; and sets of two or 

 three eyes each preferable to whole potatoes ; placing the manure 

 over the set, as the shoots pushing upward strike into it, and 

 receive immediate nourishment when in their feeblest state. 



I apprehend that the tillage the potato receives is, in general, 

 too shallow and coarse. The fibres of the potato plant, though 

 weak and delicate, spread widely and run deep when the soil 

 admits it : in alluvial ground, I have traced them to the depth of 

 4 ft., and they run across from drill to drill. Earthing potatoes 

 high in a dry soil is more prejudicial than useful, withdraw- 

 ing the mould from the roots out of their reach. It has always 

 been my practice, when the loose earth between the drills has 

 been returned on the stemSj to dig the intervals between them as 

 deeply and finely as the spade will admit, and earth no more 

 than sufficient to support the stalk. At my suggestion, a friend 

 has tried this plan on a large scale, tilling with the plough until 

 the plants were to receive the last earthing, and then sending^ 



