One of the most frustrating elements of planning a vegetable garden is finding crops to grow in the difficult spots. Most of us have at least one area that's too shady or too wet or too poor, and, for many of us, that problem area is a north-facing bed beneath a fence or wall.
NB: In particularly hot areas, north-facing walls are less of a problem. They already receive plenty of heat and reflected light, but the shade protects them from drying out quickly or suffering from leaf scorch. Here we are referring to the more common scenario where shade creates less favorable conditions...
Such a spot doesn't seem to offer much at first glance. For the majority of the year it's in shade. It's therefore colder. The soil is likely to have been neglected and the area may even be mossy. None of this sounds inviting to us, let alone a plant. However, all is not lost.
What Angle is Your Growing Area Facing?
First, check the angle your wall or fence faces. I spent a long time dismissing a bed in the garden without really looking at it. Eventually I found it didn't face due north at all and it's quite likely that yours doesn't either. If you don't have a compass to hand, there are many free compass apps for smartphones available now.
A bed facing due north will receive sunlight for only a few hours in the morning and evening during the height of the summer. If it's actually orientated slightly to the east or west, you'll find that it receives more sun than you initially thought either in the morning or afternoon. In this case, Working with Vegetables that Grow in Shade will help extend your choice of crops.
For resolutely shady spots, though, fruit is a better bet. These spots can even have advantages. In areas prone to frosts, bushes planted here are likely to blossom later and avoid cold damage to their flowers. Planting here will extend your harvesting period, as fruit will take longer to ripen than in sunnier parts of the vegetable plot.
Prepare the Bed
It makes sense to create as comfortable a spot for your fruit as possible, given the less than ideal conditions. Improve the soil with compost and ensure the pH is appropriate (around 6 – 6.5 is right). The bed is likely to be damper than average, so if you have heavy soil you want to ensure it doesn't become waterlogged. Adding compost will improve drainage. Conversely, light soil next to a wall can be quite dry, so incorporating compost will improve its water-retaining ability.
The more light the plants receive, the better (see Light: The Essential Ingredient for Good Plant Growth) so, if possible, give them the benefit of reflected light by painting the wall or fence a lighter color.
What to Grow
Red and whitecurrants, gooseberries and cherries are the main choices for a position with limited sunlight, just don't expect to grow the sweetest and richest in flavor. Culinary varieties (which are less sweet and generally need cooking before eating) are a better choice and you'll begin to notice that recommended cultivars are also often particularly disease-resistant, frost-resistant, later cropping, and heavy bearers, which compensates in part for the less than ideal conditions.
With this knowledge, you may like to pick out potential candidates for this bed yourself. Good choices, however, include the gooseberries Invicta or Greenfinch; redcurrants Red Lake and Stanza, and the morello cherry, which is the sour variety.
How to Grow Fruit with Limited Direct Sunlight
Plant fruit bushes at a wider spacing than normal: 4-5 feet (120-150 cms) apart instead of the usual 3 feet (90 cms). This is because you want them to have as much of the available light as possible and to reduce the chance of their shading each other.
One danger of a darker position is that bushes will become leggy as they stretch towards the light. This is why it's worth training them against the wall or fence in cordons or fan-shapes. This keeps legginess in check, exposes as much of the bush as possible to the light (on bushes, the branches in less light nearest the wall will be the least productive), and encourages fruiting.
By Helen Gazeley