578 



THE FARMERS' REGISTER. 



OF SEED-SOWING AND SEED SAVING. 



From Liiullcy's Horticulture. 



When a seed is committed to the earth, it un- 

 dernroes certain chemical changes be(6re it can 

 develope new parts and grow. These changes 

 are brought about by heat and water, assisted by 

 the absence of light. In many seeds the vital 

 principle is so slroni?, that to scalier them upon 

 the soil, and to cover them slightly with earth, 

 are sufficient to insure their speedy germinaiion; 

 but in others the power of growth will only mani- 

 fest itself under very favorable conditions; it is, 

 therelore, necessary to consider well upon what 

 the circumstances most suitable to germination 

 depend. 



Moisture is necessary, but not an unlimited 

 quantity. If a seed is thrown into water and ex- 

 posed to a proper temperature, the act of germina- 

 tion will take place ; but, unless the plant is an 

 aquatic, it will speedily perish ; no doubt because 

 iis powers of respiration are impeded, and it is un- 

 able to decompose the water it absorbs, which 

 collects in its cavities and becomes putrid. There 

 must, therelore, be some amount of water, which 

 to the dormant as well as the vegetating plant is 

 naturally more suitable than any other ; and ex- 

 perience shows that quantity to be just so much 

 as the particles of earth can retain around and 

 among them by the mere force of attraction. To 

 this is to be ascribed the advantages derived from 

 those mixtures of peat, loam, and sand, which 

 gardeners prefer lor their seedlings ; the peat and 

 sand together keep asunder the panicles of loam 

 which would otherwise adhere and prevent the 

 percolation of water; the loam retains moisture 

 with force enough to prevent its passing off too 

 quickly though the wide interstices of sand and 

 peat, n during the aelicate action of germina- 

 tion, the changes that the seed undergoes take 

 place without interruption, the young plant makes 

 Its appearance in a healthy state; but, if by irre- 

 gular variations of heat, light, and moisture, the 

 |)rogress of germination is sometimes accelerated 

 and sometimes stopped, the fragile machinery 

 upon which vitality depends may become so much 

 deranged as to be no longer able to perform its ac- 

 tions, and the seed will die. It is for the purpose 

 of securing unilbrmity in these respects, that we 

 employ, in delicate cases, the steady heat of a 

 gentle hot-bed, shaded ; and, in all cases whate- 

 ver, the assistance of a coaling of earth scattered 

 over the seed. 



Under what depth of earth seed should be 

 buried must always be judged of by the expe- 

 rience of a gardener : but it should be obvious 

 that minute seeds, whose powers of growth must 

 be feeble in proportion to their size, will bear only 

 a very slii>lit covering; while others, of a larger 

 eize and more vigor, will he capable, when their 

 vital powers are once put in action, of upheaving 

 considerable weights of soil. As, however, the 

 extent of this power is usually uncertain, the 

 judicious gardener will take care to employ, (or a 

 covering, no more earth than is really necessary 

 to preserve around his seeds the requisite degree 

 of darkness and moisture.* Hence the common 



* It may perhaps, be as well to notice, in this place, 

 an erroneous opinion, not uncommonly entertained, 

 that seeds must be " well" buried in order that the 



practices of sowing small seeds upon the surface 

 of the soil, and covering them with a coating of 

 moss, which may be removed when the young 

 seedlings are lound to have established them- 

 selves. In other cases, very minute seeds are 

 mixed with sand before they are sown. 



The latter practice is not, however, merely 

 for the sake of covering the seed with the smallest, 

 possible quantity of soil, but has for its object the 

 separation of seeds to such a distance, that when 

 they germinate they may not choke up each other. 

 If seedlings, like other plants, are placed so near 

 together that they either exhaust the soil of its 

 organizable matter, or overshadow each other so 

 as to hinder the requisite quantity of light, some 

 will die in order that the remainder may live ; 

 and this, in the case of rare seeds, should, of course, 

 be guarded against very carelully. 



With regard to the temperature to which a seed 

 should be subjected, in order to secure its germina- 

 tion, this, undoubtedly, various with different spe- 

 cies, atid depends upon their peculiar habits, and 

 the temperature of the climate of which they are 

 native. So far as general rules can be given up- 

 on such a subject, it may be stated that the tem- 

 perature of the earth most favorable for germina- 

 tion is 50'' to 55° for the seeds of cold countries, 

 60° to 65° lor those of " green-house plants," and 

 70** to 80*^ for those of the torrid zone. No seed, 

 however, has been known to refuse to germinate 

 in the last-mentioned temperature, although those 

 to which such a heat is necessary will not, in ge- 

 neral, grow in a healthy manner in a lower tempe- 

 rature. We have no exact experiments upon 

 this subject, except in a few cases recorded by 

 Messrs. Edwards and Colin, by whom there is a 

 very valuable set of observations upon the tempe- 

 ratures borne by certain agricultural seeds. {^/In- 

 nales des Sciences, new series, vol. v. p. 5), 

 the result of which may be thus stated : — 

 At 44 6°, wheat, barley, and rye could germinate. 



95° in icater, for three days, | of the wheat 

 and rye, and all the barley, were killed. 



104*^, in sand and earth, the same seeds sus- 

 tained the temperature for a considerable 

 time, without inconvenience. 



113°, under the same circumstances, most of 



them perished. 



122°, under the same circumstances all perished. 



But it was found that, for short periods of time, 

 a much higher temperature could be borne. 

 At 143.6°, in vapor, wheat, barley, kidney-beans, 

 and flax retained their vitality for a quarter 

 of an hour; but in 27| minutes, the three 

 last died at a temperature of 125.6°. 

 167°, in vapor, they all perished. 

 167°, in dry air, they sustained no injury. 

 It will be presently seen that some seeds will 

 bear a much higher temperature. 



The foregoing observations apply to seeds in a 

 perfisct state of health ; when they have become 

 sickly or feeble, from age or other causes, some 



young: plants, when produced, may have "sufficient 

 liold of the ground." The fact is, that, a seed, when 

 it begins to grow, plunges its roots downwards and 

 throws its stem upwards from a common point, which 

 is the seed itself; and, consequently, all the space 

 that intervenes between the surface of the soil and 

 the seed is occupied by the base of the stem, and not 

 by roots. 



