Whoever does not build or take possession of a new house, so as to have the garden to lay out himself, will, on changing his residence, probably find that the garden of his new abode requires renovating. To ascertain how far this is necessary, he has only to test every part of his garden by the principles and rules for laying out and planting which we have already laid down; and we shall therefore confine our remarks here to directing his attention to those points in which an old garden will generally be found defective.

227. The soil in old suburban gardens has frequently a sodden, black, soft appearance, and the fruit-trees are barren, cankered, and covered with moss. This is the combined effect of bad drainage, over-watering, and over-manuring. Over-watering is a common fault in town gardens; and it is particularly injurious in the neighbourhood of London, where the soil is generally clayey and badly drained, and where the soil is frequently loaded with stable manure. Most persons imagine that manure and water are all that are wanted to make a garden fertile; and, if the fruit-trees do not bear, and the flowers and vegetables do not thrive, manure and water are considered to form an universal panacea. Now, the fact is, that so far from this being the case, most small gardens have been manured and watered a great deal too much; and in many, the surface soil, instead of consisting of a rich- friable mould, only presents a soft black slimy substance, totally unfit for the purposes of vegetation, and into which the manure is changed, from being saturated with stagnant water. "No appearance is more common in the gardens of street houses than this, from these gardens being originally ill-drained, and yet continually watered; and from their possessors loading them with manure, in the hope of rendering them fertile." - (Gard. for Ladies, first edit. p. 26.) The obvious remedy for a case of this kind, is to trench the ground so deeply as to bury the surface soil, and to supply its place with the subsoil, or to mix the surface soil with lime or sand; but no remedy will be permanently efficacious if the drainage is defective. "Why is land improved by good drainage? " asks Dr. Lindley. "Many believe the whole advantage consists in removing water: but water is not in itself an evil; on the contrary, it is the food of plants, and its absence is attended with fatal results.

It is the excess of water which injures plants, just as an excess of food injures animals; with this difference, that animals can refuse what is hurtful to them, while plants have no choice, but must take into their system whatever is in contact with the spongioles of their roots. The latter therefore are more readily gorged than the former. But undrained land is not merely wet; it is water-logged. All the interstices between the particles of earth being filled with water, air is necessarily absent, except that small quantity which is dissolved in the water. In this way plants are deprived of the most essential part of their food: but when the water is removed, air takes its place, and holds in suspension as much water as the roots can thrive upon; for it is not water in a fluid state that plants prefer; it is when it has assumed the state of vapour that they feed upon it best; so that the removal of water permits air and airborne vapour, the best of all food for roots, to take its place." - (Gard. Chron. for 1849, p. 35.)

228. The underground drainage, in a garden which has been in cultivation for twenty yean, will frequently be found more or leas choked up; the indications of which are dampness and moss on certain parts of the walks, where the surface is lowest; the sodden, black, soft appearance in the soil, already described; and mossiness and canker in the fruit-trees. When the drainage is defective, there is no remedy but digging out the drains, or forming others in their stead, in the same or in preferable directions, and with fresh materials. The surface drainage, also, will often be found defective, from the ground, when the garden was first formed, having settled unequally; and this evil having been aggravated during a series of years. In cases of this kind, the hollow places formed by the sinking of the soil will hold water in pools after every heavy shower; where the walk has sunk, the gravel will have become blackened or muddy on the surface, and the box or other plant edging will look pale and sickly. There is no remedy for this but relevelling the surface; which implies taking up the gravel of the walk and its edgings, as well as such of the trees, shrubs, and plants as may grow in the hollow spaces; and, after raising the whole with fresh earth and gravel, to replace the plants.

The sewerage, or drain, from the house to the public drain or sewer, and also the means of conveying water to the house, whether by pipes from a public company, or a well or tank, should be examined. The well will most probably require cleaning, and, possibly, its sides may want to be taken down and rebuilt The same remark will apply to tanks.