Tree and shrub Shade and root problems

Part of my garden is in shade for most of the day because of the trees in a neighbour’s large garden. Since I cannot remove the trees, what can I do to improve the conditions for my plants? And what plants will grow well?

If the trees grow close to your garden the shade will be dense, and the soil is likely to be permanently moist from overhead drip. Improve the drainage with coarse grit, and plant moisture-and shade-loving plants such as hardy ferns, Primula species, violets, and periwinkles. Lighter and more dappled shade is no problem, as there are many plants which prefer this kind of light: lilies, hostas, azaleas, rhododendrons, and blue poppy (Meconopsis) are a few examples.

The soil beneath my large horse chestnut is very dry for most of the year and the lawn grass will not grow in its shade. What can I grow instead to keep weeds and moss at bay?

The dwarf cyclamen should do well; small-leaved ivies and epimedium will also grow there. If you mix plenty of peat and some general fertiliser into the soil, many more plants will grow, since this treatment will introduce food and water to the soil.

The roots of a nearby poplar tree are showing above the surface of my lawn and are sprouting shoots. If I treat these leaves and shoots with hormone weedkiller, will it kill them—but also kill the tree?

The solution will kill the treated shoots but not the tree. However, more shoots are likely to appear and will also need treatment. Either increase the depth of lawn soil by topdressing to cover the exposed roots, or mow the shoots off regularly.

I’ve heard a lot about the trouble tree roots can cause to the foundations of houses, and am wondering whether the roots of the cedar planted in our front garden are likely to be a problem.

The tree roots which penetrate foundations are mainly those of poplar, elm, and willow—large, vigorous, and widely extending trees—and the trouble occurs most often on clay soils. In general, it is wise to avoid planting a tree within 5 m (16 ½ ft) of the house. Even if the roots of your cedar do little damage, the branches will eventually cast shade into your rooms; and they could damage the fabric of the house if they broke off in a gale or a heavy snowstorm.

What are my legal obligations regarding trees which overhang a neighbour’s garden? Do I have to cut them back? And what about the roots?

No, you need not cut overhanging branches back, though your neighbour is entitled to cut them back to the boundary of his garden. Such cut-off branches, however, will still legally be yours, including any fruit on them. Roots which ‘trespass’ are a different matter, and if they damage walls or foundations you will be held responsible. If you wish to cut down one of your own trees completely, make sure it does not have a preservation order on it for reasons of rarity, amenity, or whatever. In certain cases a tree can be cut down only if it is replaced by one of similar dimensions and appearance. Your local council will be able to clarify the situation on any particular tree you may have in mind.