Under certain conditions it is possible for gardeners to modify the life of a cherry, and to make it bloom much earlier, but this is only possible within well-defined limits. It is no use trying to force it to bloom before January. It _must_ have a quiet time after summer. But by beginning in January and by very carefully managing the temperature, it can be made to produce fruit quite early in the year. The following account is given to show how very carefully gardeners have to work when they upset the ordinary course of Nature's events. The plant is taken into a greenhouse, and the temperature kept as follows:-- Day Night Temperature. Temperature. First week 48°-50° F. 41°-45° F. Second week 50°-53° F. 45°-48° F. Third week 53°-59° F. 48°-51° F. Till flowering 59°-64° F. 51°-57° F. Flowering period 46°-53° F.(!) 43°-50° F.(!) After flowering 59°-64° F. 51°-57° F. During development of stone 53°-59° F.(!) 48°-51° F.(!) After development of stone 61°-66° F. 53°-59° F. Ripening of fruit 68°-70° F. 59°-63° F. Not merely strong, forcing heat, but a little judicious cold, is necessary to get out the flowers and to ripen the fruit.[43] [43] Schimper, _Pflanzengeographie_. The account is based on the works of Pynaert, Sachs, Askenasy, etc. Most flowers have very much the same general history as the cherry, but it must not be supposed that they are all alike. The differences are very interesting and curious. Thus, for example, plants of our common Gorse, furze, or whin may be found in bloom at almost every season of the year. There are at least four seasons when there is that tremendous display of golden blossom which made the great Linnæus fall on his knees and burst into tears. These are about the 22nd March, 24th May, 15th August, and 21st November; yet there are enough odd flowers blooming in almost every month to give some cause for the saying, "The gorse is out of bloom when kissing is out of favour." The last practice, though uncleanly and dangerous, not only on general grounds, but on account of bacterial germs which may be transferred, has been authoritatively condemned in the United States, but it is still more or less popular in other countries at all seasons. The Chickweed and some other of our annual weeds show a hardy disregard of climate. Its seeds germinate and grow at any time, so that flowers and seeds can be formed whenever there is a spell of favourable weather. Now one chickweed can produce 3000 seeds. Suppose that there are only five generations in the year, which is a very low estimate. Then one seed of chickweed might produce 3000 × 3000 × 3000 × 3000 individuals in one season!