Cosmos Plant 'Cherry Chocolate'

How To Grow Perennials

Seedlings & Plug Plants

Once your seedlings or plug plants have been delivered, remove them immediately from their packaging. Place them in a shallow dish of water for a few minutes to soak the plug of compost. Ideally, these should be potted on immediately or if not, within a day or 2, keeping the plugs indoors in a warm and sunny place and ensuring the compost plug does not dry out. You may need to turn the plugs around as they will start to grow towards the light.

Potting on Plugs:

When you are ready to pot the plugs on, lift them by their leaves, not the stem, as these bruise easily and can cause disease to enter and kill the plants. Pot into 9cm pots filled with potting on compost by making a hole big enough for the plug to go into. Plant so the seedling leaves are still proud of the surface. Tap to settle the compost and give them a good water.

Hardening off:

Once your potted on plants reach approx 15cm (6in) tall and they are ready to plant out in their final location, the first step is to harden them off before moving them outdoors permanently. This involves simply placing them outdoors during the day and back undercover at night to allow them to get accustomed to the lower temperatures. Once they have been hardened off for a week your plants should be ready to plant out in their final location.

Final planting of seedlings & plugs:

Once the final frosts have passed, your plugs can now be planted in their final position. Choose decorative patio pots or in the garden borders. Best to use peat free compost or general-purpose compost. Water your compost before planting. Make a hole the size of your pot and plant up to the same level as the original pot. Water again to settle the compost around the root ball.

 

Bare Root Perennials

Soak the roots in a bucket of cold water for around an hour before planting to help hydrate the plant.

Dig a hole that is deep and wide enough to take the entire root mass. Place the plant in the hole and spread the roots out; the main stem should sit just above the surface of the soil. Fill the hole with soil and firm around the stem of the plant with your hand, or you can use your foot for larger perennials. Give them a good watering.

Garden Ready Plants and larger planting instructions:

Perennials in sizes Garden Ready Plants, 9cm, 1L, and larger, unpack and if the weather is favourable, put outside as soon as it arrives and give it a water.

When ready to plant, ensure it’s positioned in the right location and aspect in the garden.

Keep the area around it clear to avoid overcrowding which reduces its establishment and growth.

Dig a hole approximately twice as deep and 3 times as wide as the plant’s rootball. If your soil is heavy, mix in a soil improver before backfilling. We also recommend adding plant feed into the hole before back filling to help establishment and growth.

Place the plant in the hole so that it sits at the same level in the ground as it did in the pot. Firm the soil around the plant and water thoroughly.

Feeding and aftercare: Keep it well watered and fed for establishment and growth. Can be mulched in autumn/spring each year.

Planting and Flowering Months:

Planting and flowering months are subject to seasonal weather conditions. Recommended planting months for each variety are displayed on each product page. Large perennials over 9cm can be planted for almost all months of the year but take extra care during the cold winter months to avoid frost and hot summer months with extra watering.

Guide to Perennial Plant Sizes

Our Perennial Plants come in sizes from Seedlings up to 7.5L. Different sizes are at different maturity levels which alters their planting instructions.

Seedlings

Selected by our team of experts and sent from our nursery, you will receive your Seedlings in plug trays in a box. These are designed to keep your plants secure and to prevent damage in transit. Seedlings will require growing-on and hardening off in larger pots, please read our ‘How to grow’ guide.

Plugs

Plug plants are larger and more mature than our seedlings, you will receive your Plugs in plug trays in a box. Plugs will require hardening off in larger pots, please read our ‘How to grow’ guide.

Garden Ready Plants

Our largest, most mature Plug plants, you will receive your Garden Ready Plug Plants in plug trays in a box. Garden Ready Plants are mature enough to be planted straight out into its final position.

9cm, 1L and Larger

You will receive your plant in a pot.

If you have ordered your perennial during autumn or winter, it may appear yellow or have no flowers/leaves. The plant is still healthy and ready to plant straight out into its final position but looks different during different seasons.

Bare Root Perennials

Delivered without a pot or compost, Bare Rooted plants are dormant plants. Don't be fooled by their appearance - bare roots are bursting with energy and planting them in autumn and winter is the best way to guarantee strong, healthy and thriving plants in spring and summer. Bare Roots require soaking in water before planting, please read our ‘How to grow’ guide.

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Seedlings need a fine Young Plant Compost.

Plug Plants need a Potting On Compost.

Established plants can use a Peat-Free Compost