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Perennials - Flowering Seasons
Perennials - Guide
Many outstanding plants are perennial, either forming clumps, for instance the Agapanthus, or producing a single, soft crown, like the Impatiens. Some may be evergreen, others being herbaceous, dying down to dormant roots. The dying down during winter is due to drought and frost, but will re-emerge in warmer times. Perennials require careful tending regarding soil fertility and mulching, cultivation, weeding and clearing the plant of dead foliage. Planted with specimens of other growing habits, you can create an exciting border, always different and new.
Preparing and planting…
Growing in one place with a rather limited root system, thorough bed-preparation is essential. Start by working and breaking up the soil to at least 30cm deep and remove any foreign matter. Work the soil through until a fine texture is obtained. Enrich the soil with well-rotted, old manure or organic matter. Mix the soil/matter-combination thoroughly, again to the depth of 30cm. Add right before planting Superphosphate and 2:3:2, 60g of each p/m². Rake your soil surface to an even level and plant away!
For single crowned perennials
severe cutting is in many cases necessary, up to three times annually, for these plants often become straggly and woody and sometimes even dies down eventually. With plants like Argyranthemum frutescens on the other hand, cutting back could prove to be fatal. These soft perennials are more complicated than its clump-forming siblings are, due to its inability to lie dormant during winter months, and could die because of it. Fertilise with 2:3:2 every six weeks and water regularly. Apply new layers of mulch seasonally with bark, old manure or matter of your choice.
For clump-forming perennials
the most important aspect is lifting, dividing and replanting after flowering. Those not included in this requirement are minimal.
When dividing clumps, you need to…
Water the plant thoroughly a couple of days before lifting and cut back foliage and stems to 5cm above the ground.
Lift plants carefully, place in a shady spot and protected with damp cloth. Prepare new planting beds as before.
When ready to plant, divide the plants to single crowns, gently with your hands or sharp knife and plant immediately, no more than eight-p/m ². Give plants a generous soaking afterwards.
Water thoroughly, twice weekly, and fertilise with 2:3:2 every six weeks. Do not water or fertilise dormant perennials during cold winters. Mulch seasonally with straw, bark, old manure, decayed foliage or matter of your choice. Cut dying foliage down to a couple of centimetres above the ground before dormancy period start.
Note: some plants may be grown in regions with frost, but is mentioned under areas with NO FROST, for they will grow better under those conditions.
Perennials can provide foliage and colour to any space needed of attention.