Filberts and Cob Nuts.—­These Nuts will succeed on any soil that is not cold or wet.  The bushes should be planted in October, when the leaves have nearly all fallen.  Make the soil firm about the roots and give a mulching of stable manure.  At the beginning of April the old and exhausted wood may be cut away, as well as any branches that obstruct light and air.  Encourage well-balanced heads to the bushes by cutting back any branch that grows too vigorously, and remove all suckers as they make an appearance, except they are required for transplanting.  The crop is produced on the small wood.  The best method of propagation is by layers in November or any time before the buds swell in spring.  The process is simple, it merely requiring a notch to be made in a branch of two or three years’ growth, which is then pegged down 2 or 3 in. below the surface.  The following autumn it may be cut away from its parent, pruned, and planted.  They may also be grown from nuts sown in autumn and transplanted when two years old.  In Kent the bushes are kept low and wide-spreading, by which means the harvest is more readily reaped.  On a fairly good soil they should stand from 10 to 14 ft. apart.  Lambert’s Filberts, Frizzled Filberts, Purple Filberts are good varieties, the former two bearing abundantly.  Among the best of the Cobs may be mentioned the Great Cob and Merveille de Bollwyller.

Fire Thorn.—­See “Crataegus.”

Flea Bane.—­See “Inula” and “Stenactis.”

Flower-Pots, Sizes of.—­Various practices prevail at different potteries, but the appended names and sizes are generally adopted.  In every case the inside measurement is taken.

Inches     Inches
SIZES.                          across Top.    Deep.

Thimbles                            2         2
Thumbs                              2-1/2     2-1/2
Sixties (60’s)                      3         3-1/2
Fifty-fours (54’s)                  4         4
Forty-eights (48’s)                 4-1/2     5
Thirty-twos (32’s)                  6         6
Twenty-fours (24’s)                 8-1/2     8
Sixteens (16’s)                     9-1/2     9
Twelves (12’s)                     11-1/2    10
Eights (8’s)                       12        11
Sixes (6’s)                        13        11
Fours (4’s)                        15        13
Threes (3’s)                       17        13
Twos (2’s)                         18        14

Foam Flower.—­See “Tiarella.”

Fontanesia Phillyraeoides.—­This shrub will grow in any soil, but needs protection in severe weather.  It may be propagated by layers or by cuttings planted under glass.  August is its time for flowering.  Height, 10 ft.

Forget-me-not.—­See “Myosotis.”

Forsythia.—­Any good soil suits these pretty shrubs.  F. Suspensa thrives best under greenhouse treatment, but F. Viridissima is quite hardy.  The former flowers in March, the latter in February.  They may be increased by layers or cuttings.  Height, 10 ft.