Finishing touches (reinstalling plants; edging and mulching)
Plan to reset the plants into the renovated bed in late afternoon, when the sun is low in the sky and they can readjust in cool darkness overnight. Consider new placements for perennials returning to the border, moving some into better positions and grouping others in complementary partnerships. This is also a good opportunity to record the new locations for future reference. Move the stored plants into position on top of the amended soil and decide on their final placement. If space permits, newly purchased plants can be added to the bed.
Before each perennial clump is replanted, consider if it needs dividing. Divisions can be used to increase the display or given away. Reset the plants into the soil, mixing two trowels of compost or composted manure into each hole; water in each plant. In spring, a transplant solution can be added to the water. (Transplant solution isn't used in autumn, when it could stimulate late growth just before frost.)
Once all the plants are installed, use a blunt-nosed spade or half-moon edger to finish the bed with a neat, sharp line. Finally, spread a five-centimetre layer of organic mulch (small or shredded leaves, or purchased shredded bark mulch) to protect the amended soil from erosion, suppress the growth of weed seeds and keep plant roots cool. Cover exposed soil and surround the crowns of perennials, but leave a five-centimetre gap around each crown to prevent smothering or causing decay to lower stems.
Building soil fertility
Natural fertilizers from plant and animal sources provide necessary nutrients and trace elements in low concentrations that won't shock new transplants. Homemade garden compost and composted manures (usually less than two per cent nitrogen) are good sources of plant foods that won't burn roots and can be used throughout the season. Leaves, shredded or whole, incorporated into garden soil or used as a surface mulch, will encourage worms to establish colonies and distribute their nutrient-rich castings throughout the soil.
Alfalfa contains five per cent nitrogen and the natural growth stimulant triacontanol. It's sold as an animal feed in small bales or as ground meal or compressed pellets. (Pet supply stores often carry alfalfa.) A handful of any form of alfalfa can be mixed into the soil in planting holes to provide a nutritious meal for perennials in any season.
A handful of fish meal containing five per cent nitrogen can also be mixed into planting holes. Keep in mind, however, that if raccoons are frequent visitors to your garden, they'll be interested in fish meal and may dig up plants.