Watering of areas of new perennial planting

• Avoid a routine such as “watering once a week”. Plants need different amounts depending on the variety, weather, soil type, stage of establishment and size. In their first year, water around the base of the plant until the soil is evenly moist down to the depth of the roots – typically 15cm (6in). After the first year, established perennials usually do not need watering as regularly.
• Use a watering can with a rose attachment, or a hose on ‘spray’ setting. This is important to avoid compacting the soil around plants, and to avoid exposing fine roots by removing the topsoil around them by using powerful water jets.
• Water should be applied directly to the base of herbaceous plants to ensure that it gets to the root zone. Newly planted perennials are likely to be planted in C2 pots that measure roughly 17cm across, so the roots will initially be restricted to this size. Watering done through a sprinkler is often ineffective as it will deliver large amounts of water to the plant’s foliage and the surface of the soil where it will quickly evaporate in warm weather. Ensure that any water used is delivered to where it is needed.
• In the second and third year after planting, watering can be reduced as the plants will have established their roots to find water for themselves. Planting will still be vulnerable to heat waves and droughts, and if plants start to wilt in hot dry weather this is a sure sign of water stress. Act quickly to water these plants deeply and they should perk back up quickly.
• Evergreen perennials continue to take up water in the winter, and if there is a rare dry spell through winter then a little water may be required though this is very unusual.
• Just because it’s been raining doesn’t mean your plants will have has had enough water. Rain often doesn’t reach the root ball directly, especially if the planting is in a rain shadow, such as planted beneath a mature tree, next to a fence or wall, or sheltered beneath the eaves of a house. Continue to water these plants even after light rain.
• If you are unsure about if a plant needs more water then it can be inspected by hand. Gently move a small amount of soil to one side by hand and push your finger into the soil to feel if the soil is dry, slightly damp or soggy. You want the soil to feel evenly moist, rather than completely saturated with water. One year may be a particularly cool wet summer, while the next may be an unusually dry summer with days that regularly exceed 25-30c. The watering requirements will differ in each of these years.
• As important as it is to keep new planting well watered to ensure it establishes well, it is just as important not to over water. Key signs include yellowing foliage, soft or rotting growth and wilting. To check if the plants are being over watered, see if the surrounding soil is very wet or saturated, if so leave it to dry out for a few days until it is evenly moist before adjusting your watering regime.
  
  

Fertilising areas of new perennial planting

• Provided the plants have been planted in a good quality soil, most plants will enjoy good health and make satisfactory growth without the need to fertilise. Some plants such as ornamental grasses, Achillea and Echinacea prefer a soil with low fertility. Planting areas can be top-dressed with slow-release fertilisers can be applied in autumn and are available from most garden centres. Be sure to follow instructions carefully as dosages vary among products, and using too much fertiliser can cause chemical burns to plants.
• All of the potted perennials that we supply come with slow release fertiliser from the nursery, this will usually be enough to get the plant established in the first season, 
• A liquid feed such as liquid seaweed or a general liquid fertiliser can be used for more instant results, and plants such as annuals, vegetables, and plants grown in containers can really benefit from this type of liquid feed. Ensure that the correct dosage is used as using too much fertiliser can cause chemical burns to plants.
• If you use a ‘weed and feed’ product on your lawn, ensure that this isn’t used too close to areas of planting as ‘weed and feed’ products contain herbicides that target broadleaf plants.

General care of grasses and perennials

• Ensure that grasses are cut back before any new growth starts, or just as the new growth appears. If cutting hard back is left too late then this can make the grass look messy or be too congested to grow to their full potential.
• The same applies to herbaceous perennials such as Verbena ‘Bampton’, Penstemon, and Salvia nemorosa species. A good cut back at the start of the year is essential to open the plants up and give the new growth space, while also allowing good airflow to discourage pests and diseases.
• Some perennials, once established, can be left to fend for themselves with minimal water. These are generally limited to highly drought resistant plants such as Stachys byzantia, Achillea millefolium, and Rosmarinus sp.
• In our maintenance guides, we often recommend leaving plants with decorative seedheads to stand over winter for the sculptural interest and benefit to wildlife. This is a personal pereference and if plant seedheads start to look too messy or untidy after a heavy rain or storm then they can be cut back sooner.
• Ensure that the planting area is kept well weeded as weeds compete with your plants for light, water and nutrients. Weeds can also smother newly planted ornamentals causing them to die off or perform sub optimally due to competition. It is important to quickly learn what is a weed and what is a desirable plant to keep in the garden.