Forking over is the standard autumn technique to get the soil of the herbaceous or mixed border ready for its winter rest. Choose a day in late autumn when the soil is moist (not wet) and free from frost. Work from the back of the border towards the front or from the centre of the bed to the edges – use a fork to break up the surface crust, turning over the top couple of inches of soil between the plants. Do not disturb the, but stop every time you find a perennial weed and dig it out.
Incorporate the mulch you put down in spring into the soil – leave the surface rough. Forking over is an enjoyable job to do on a sunny day in autumn, and it probably does you more good than the plants unless your soil is heavy and prone to severe crusting and mossing over.
Perennials which are not completely hardy present a problem – you can trust to luck but in many areas a severe winter will undoubtedly mean their death. You can cover them with glass cloches but it is more usual to put a blanket of straw, bracken,mould or peat over the crowns. Anchor this cover down with twigs, and don’t forget to remove it in spring when new growth begins to appear.
Delicate but hardy alpines need protection from winter rains rather than from frosts. The standard method is to cover the plants with a pane of glass supported by bricks.
Flowers, like all other living things, require food. The production of, , and is a drain on the soil’s reserves of nitrogen, phosphates, potash and several other elements. If one or more of these vital elements run short, then hunger signs appear on the leaves or flowers and both vigour and are affected. The answer is to apply fertilizer at some stage or stages of the plant’s life.
The golden rule is that there is no single technique which can be applied to all plants. The nutrient requirements of a tiny alpine and a large-floweringmust be different, and yet the alpine is often over-fed and the large perennials starved.
Work a powder or granular fertilizer into the surface during soil preparation prior to planting. The nitrogen content of this fertilizer should never be higher than the phosphate or potash content – for border perennials and bulbs use Growmore, foruse Growmore or Bone Meal and for rockery perennials use Bone Meal. Check with the A-Z guides before taking this step – a few plants grow best under starvation or infertile conditions and should not be fed.