This section is from the book "The Gardener V1", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
Old-established trees with their roots in narrow inside borders, that are bearing heavy crops, will require copious waterings of manure-water to keep the border moist. Syringe the trees every fine afternoon until the fruit begins to ripen, when the house must be kept drier. Let the night-temperature range about 60° unless it be very mild, when it may be 65°. Tie the young growths to the trellis, and avoid crowding them. In fact, no more young wood should be left than is enough for next year's crop.
These will be swelling their crop rapidly, and those started in December should begin to ripen before the close of the month. Up till the time of ripening, keep a moist atmosphere, and syringe the trees freely every fine day at shutting-up time. When the first signs of ripening are noticed, discontinue syringing, and otherwise decrease the moisture and ventilate more freely, so as to keep a circulation of dry warm air about the trees, that the Figs may be well-flavoured. Let the night temperature be 65°. When the second crop is well developed on the young growths, thin them out in time. A fair crop of large well-swelled fruits is much to be preferred to a greater number of inferior quality. Attend to the tying of young growths on succession-trees, and do not crowd the foliage by retaining more growths than are needed to furnish the trees. See that all trees in pots or restricted inside borders are well supplied with water, giving frequent applications of manure-water.
Whenever the first crop is gathered from early forced trees, give them a good watering with manure-water, and syringe them every afternoon. Thin off the second crop if there is more than sufficient for a good crop. Ripening fruit should be well ventilated to bring flavour to the highest pitch. Young trees in luxuriant growth and not bearing freely should not be stimulated, but watered with pure water.
Where fruit are ripening cease the use of the syringe, and give a free circulation of air. When the first crop is all gathered, and the second coming on, see that the trees are well nourished with manure - water, and syringe them freely every day at shutting-up time. Trees in pots or tubs must be very carefully attended to with water, and never be allowed to get over-dry. Any old mulchings of manure applied to these early in the season should be removed down to the roots, and a fresh dressing of rich manure put in its place, so that the second crop of fruit may be well sustained, and. the trees in every way kept in good order.
Early trees, on which a second crop is now swelling, should be liberally supplied with manure-water until they begin to ripen, when less will be necessary. When ripening, keep the air dry, and give abundance of it. Early pit-trees, from which their second crop may be gathered by the end of this month, should be kept as cool as possible; give them an occasional syringing to keep the foliage clean, and see that they are never allowed to sufer for want of water at the root. Any shoots not considered necessary should be removed at once.
Let trees swelling off crops be encouraged by waterings of manure-water. Give plenty of air to those ripening, and syringe trees from which all the Figs are gathered, to keep the foliage clean and healthy. Plants in pots from which the second crop is all gathered may be placed in a sheltered warm spot outdoors; but see that they are never allowed to suffer for want of water.
Generally speaking, all Figs are gathered by the end of this month; but where any are to ripen they should have fire-heat applied, or they will not be good. All wood not required to furnish the tree properly should be removed at once; but when disbudding has been duly attended to, there will be very little that it is not necessary to retain. Early plants in pots should now be protected from excessive rains, and watch inside borders, keeping them in a medium state of moisture.
Prune and tie as soon as all the leaves are fallen. This, of course, refers to late trees, for the early ones are leafless long ago. Like all other fruit-trees, Figs are often tied in too thickly, and this evil should be avoided. Remove the surface - soil of inside and restricted borders quite down to the roots, and cover them with some fresh loam with which horse-droppings and bone-meal is liberally mixed. Keep plants and pots cool and airy all through this month, but see that they are not allowed to become over-dry at the roots.
Where early Figs are in demand, a light pit or low house should be got in readiness, where trees in pots can be started after the middle of the month. Bottom-heat from a bed of leaves is of the first importance in early Fig-forcing. It should not exceed 80°, and the air temperature should be from 50° to 55° the first month. To secure this, very little fire-heat is required, if the pots be plunged in a bed of oak-leaves. Syringe the plants several times a-day, and see that they are kept steadily moist at the root with water, at about 80°. As soon as ever the buds begin to move, top-dress the pots with loam and horse-droppings.