This section is from the book "The Gardener V1", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
In ordinary soils and situations, little difficulty in general is experienced in securing a plentiful supply of that esteemed vegetable the Pea after midsummer and during early autumn; but unless where conditions are favourable to their respective wants, early and late supplies cannot be calculated upon with such a degree of certainty. In this paper I do not presume to advance any new cultural theory on the above vegetable, but thinking that a few notes on some of the conditions necessary or at least desirable in cultivation of early and late crops, might not be amiss to some readers of your esteemed serial, I beg to offer them. In some cases the idea is entertained, that according to the shelter afforded them will Peas be early or late. But this idea, although both reasonable and natural, is not invariably correct, as a good deal depends on the nature of the soil in different gardens or localities. Light and rather shallow soils, although not equally capable, with deeper and more holding soils, of maintaining the same duration and quality of produce, are best adapted for early crops; and of course a well-sheltered and sunny aspect will be additionally favourable.
An instance demonstrating the different effects of soils in maturing Peas came under my observation last summer which it may not be out of place to record here. In sowing what I expected the latest supplies from, early sorts were used - viz., Sangster No. 1, two sowings of which I put in on 10th and 25th of June respectively. Despite the fact that the latter sowing occupied the most shady quarter, the crop was ripe some fortnight before the other was fit for table. I have no other way of explaining it than that the soil in the quarter where the latter grew is very poor and shallow, and the crop depended mainly on an application of rotten manure, thrown into the drills (which were made with a spade) before sowing; while that on which the former was sown is good ground some 4 or 5 feet deep.
Referring briefly to late crops, I would observe that, as in early crops, locality and soil have much to do with the success or failure of the cultivator, the latter perhaps having the most direct influence in this respect. In dry seasons particularly, Peas for a late supply, sown on light shallow soils, are very liable to severe checks in their growth, in consequence of which they are prematurely thrown into bloom, when the object of the cultivator is at once defeated. Such results, it is true, are sometimes modified by regular attention to mulching, applications of liquid manure, etc.; but even such precautions, with light soils and in dry seasons, are often labour in vain. The Squire's Gardener, in his paper on the rotation of crops some time ago, made a very practical remark in concluding - viz., that the character of the soil in many gardens compelled the cultivator to localise many crops; and to this observation we would recommend those of your comparatively inexperienced readers to take heed, as in the case of Peas it is particularly applicable.
It is at least a step in the right direction to reserve in spring (according to demand) a piece of good ground (rather heavy than otherwise), which has previously undergone deep tillage and been well manured, on which to sow late Peas. Those cultivators who may not have such resources at their disposal, in dry seasons at least, are not warranted, if I may so speak, to expect success in growing late Peas. I was at one time led to believe that ground intended for Peas should be manured sparingly, but have since perceived that such a rule could not be adopted indiscriminately. To rich heavy loam or clayey soils this rule may apply to some extent, but in regard to those of lighter and more open consistency, liberal manuring is necessary, and for late crops in particular, as it enables them more effectually to cope with long periods of drought, to which they are occasionally subjected. Late crops should be rather thinly sown than otherwise, as I think by taking this precaution their bearing period is prolonged. Regarding the best varieties for late supplies, certain sorts will probably succeed better in some localities than in others.
Here, in the Western Isles, with a uniformly humid atmosphere, Veitch's Perfection and Champion of England, two good old sorts, have these two last years yielded produce till the latter part of September. In fact, the former last season afforded supplies much longer than the sowings I previously referred to, which were originally intended for the latest supply.