The gentle hues and varying textures of cottage garden perennials can be used to create beautiful combinations in an informal planting design. This is the classic sun-loving border of many gardeners’ imaginations, with spires of lofty delphiniums piercing through lower mounds of colorful flowers.
When to plant: Autumn.
At their best: Midsummer.
Time to complete: 2 hours preparation; 3 hours to plant.
You will need: Spade, well-rotted organic matter, grit.
Selection of plants to use: Delphinium Black Knight Group, Anchusa azurea, Alstroemeria ligtu hybrids, Achillea filipendulina ‘Gold Plate’, Salvia sclarea var. turkestanica, Verbascum olympicum.
Prepare the soil
In autumn, clear the border of all weeds. Dig in organic matter, such as garden compost or well-rotted manure. Ideally you should dig down one spade depth, incorporating organic matter into the top 6 in (15 cm) of soil. On heavy soils, spread a layer of grit over the whole area, and dig it in to improve drainage.
Set out the planting plan
Buy plants in spring and set them out across the border, taking time to arrange them and to visualize how they will grow in relation to each other. The classic arrangement is taller plants at the back and shorter plants at the front, but consider using tall, airy types, such as Achillea or Verbena bonariensis, farther forward.
Some of the plants will need staking as they grow, and in their first year they will require regular watering to help them establish. Although these herbaceous perennials die back in winter, where possible, leave their stems to stand until spring. Then cut everything back to the ground to neaten the border and allow space for new growth. This is also a good time to apply a general-purpose granular fertilizer and a mulch of well-rotted organic matter.
Many perennials, such as delphiniums and Achillea, become top-heavy and require support. If you provide supports early in the season, plants will grow through and disguise them, and they will still look natural and attractive. Plants staked at a later date, once they have already flopped, tend to always look trussed up.