fiutill'aria. 



Ill 



FROST. 



a 6tratum of air, which, from its non- 

 conducting power, greatly lessens the 

 escape of heat through the mats. As 

 mats are apt to ahsorb the rain in- 

 stead of conducting it off, coverings of 

 thatch formed of regularly drawn 

 wheat-straw or reeds are considered 

 preferable ; though such roofings are 

 scarcely worth attending to in a small 

 garden, where there is perhaps only 

 one frame. The best covering of all 

 is composed of boarded shutters, 

 placed a few inches distant from 

 the frame, and this species of. 

 shelter is at once neat and durable, 

 and calculated to retain a stratum of 

 air above the glass, while it effec- 

 tually throws off the rain. — See Hot- 

 beds and Pits. 



Franco'a. — Francoaceoe, or Ga- 

 lactnece. — Handsome plants, most of 

 which may be treated either as an- 

 nuals or perennials, and may be 

 always raised from seed. They are 

 nearly hardy, and will grow in any 

 common garden soil. F. ramosa, 

 with white flowers, is generally kept 

 in the greenhouse, and will not admit 

 of being treated as an annual. 



Franke^nia . — CaryophyllacecB. — 

 Sea heath. Dwarf perennials, which 

 should be grown in pots, or on rock- 

 work, in a mixture of loam and peat, 

 and which are increased by seeds, or 

 cuttings. 



Fraxine v lla. — See Dicta'mnus. 



French Berries. The fruit of 

 Rhdmnus tinctorius. — See Rha'm- 



■ KUS. 



French Honeysuckle. — See 

 Hrdy'sarum. 



French Marigold. — SeeTAGE^TEs. 



Fringe - Tree. — See Chiona'n- 

 thus. 



Fritill v aria. — Tulipacece. — 

 Hardy bulbous rooted plants, which 

 will thrive in any common garden 

 soil ; but which do best in sandy 

 loam. There are several species. 

 They are increased by offsets ; and 



they may remain several years in the 

 ground without taking up, and with- 

 out receiving any injury. 



Fritillary. — See Fritill^aria. 



Frogbit. — Hydrocharis morsus- 

 rance. — A very graceful aquatic, 

 with white flowers. 



Frost is injurious to plants in 

 proportion to their natural tender- 

 ness, and to their succulency, whether 

 induced by art, by culture, or the 

 season, or the accidental or natu- 

 ral moisture of the soil. Hence, to 

 protect plants from frost, the first 

 step is the thorough drainage of the 

 subsoil ; and the next, the use of a 

 soil composed of materials which will 

 readily permit the escape of water, 

 and which, of course, is always com- 

 paratively dry. On such a soil, if a 

 frame covered with glass sashes be 

 placed, and covered with mats, thatch, 

 or boards during severe nights, all 

 half-hardy plants will be completely 

 protected. But there are a great 

 many plants in beds, and borders, and 

 against walls, which cannot be conve- 

 niently protected by these means ; 

 and the roots or lower parts of the 

 stems of plants thus situated may be 

 covered with leaves, straw, litter, 

 rotten tan, or any other dry non- 

 conducting material which will retain 

 air, and consequently prevent the 

 escape of heat, and yet throw off 

 water. In general, all herbaceous 

 plants may be entirely covered during 

 winter with such kind of materials ; 

 and all ligneous plants will be saved 

 from being killed, if the root-stock, 

 neck, or collar, be so covered. The 

 branches and upper part of the stem, 

 if left naked, may indeed be de- 

 stroyed ; but if the collar and the 

 ground for two or three feet around 

 it be thus protected, the life of the 

 plant will be preserved, and the next 

 spring, if the plant be cut down to 

 the ground, it will spring up again 

 from the collar. In general, the 



