JULY. 345 



But independently of the risk we run in planting out before we have 

 settled, mild-growing weather, it is also of great import in a season like the 

 present, that the ground should attain its natural heat before tender plants 

 are committed to its fostering care. A week or two back we were told that 

 nettle seed would not vegetate at the same temperature as groundsel, and 

 that the generality of exotic seeds would not vegetate in a temperature be- 

 low 46°. I have just been testing the temperature of the soil in the flower 

 garden here, and I find it range from 44° to 46° at from 9 to 12 inches deep, 

 according to the exposure and the time the beds were last digged, — the 

 highest temperature, that of 46°, only being found in a bed that was dug 

 on a sunny day a fortnight back. Now, the mean temperature of the earth 

 at one foot deep, as explained by an important table in Dr. Lindley's "The- 

 ory of Horticulture" just published, is April 46°, May 53°, and June 60°. 

 The lowest temperature for May was in 184.1, viz., 50°, the highest for the 

 same month in 1848, 56° ; the lowest temperature for June is 56° in 1852, 

 the highest 64° in 1846. Thus it will be seen that the ground at the pres- 

 ent time, is 4° colder than it has been known since 1844, and 10° below 

 the highest temperature during the same period. Need we then be sur- 

 prised if plants make slow progress ? It is physically impossible that they 

 could do otherwise until the earth attains something like its natural temper- 

 ature, and the more plants are watered under such circumstances, except 

 with water very considerably warmer than the soil in which they are grow- 

 ing, the greater the injury they must receive. To drench plants with cold 

 water at the present time, is labor worse than lost. But what is to be done ? 

 To plant even now until the earth has attained a temperature of 55°, will 

 not be a wise proceeding, yet plant we must. Fifteen years back, in my 

 treatise on Cucumbers in pots, I recommended the " digging in" of solar 

 heat for ridge cucumbers, and I should now advise the same process to be 

 observed with all flower beds that are not stocked with plants. By forking 

 the beds over after four o'clock every sunny afternoon for a few days, mak- 

 ing or raking the surface of the ground tolerably fine, its temperature may 

 be raised from 6° to 10° in a very short time, and it is I think quite unnec- 

 essary for me to explain that an increase of bottom heat, at the time of 

 planting to that amount, is a matter of much greater importance than hur- 

 rying the roots of plants into the ground the first fine day, just because the 

 sun is shining or the air overhead is a little genial. What I am recom- 

 mending is just what I have practised for many years, and if those who do 

 not happen to think on this matter as I do will please to make the experi- 

 ment, I know they will be satisfied with the result. Let them get heat into 

 the soil, then plant and give a sufficient watering with warm water, and 

 when it has soaked in, leave the surface of the soil loose, fine and smooth, 

 and little after- watering, unless the weather is very dry, will be found 

 necessary. Daily dribblings of water may be all very well to occupy the 

 leisure hours of amateurs, " who have nothing else to do;" but gardeners, 

 and those under them, may spend their time far more profitably. — ( Gard. 

 Chron. May, 1855, p. 356.) 



VOL. XXI. NO. VII. 44 



