Rosa Robusta = 'Korgosa'

Autumn-Spring · Planting

Planting "bareroot" roses

A "bareroot" rose is supplied without soil around its roots, the roots are dry and the rose is in a dormant state. Before planting a bareroot rose, soak the roots in a bucket of water for 2 hours to rehydrate them. Plant the rose between late autumn and early spring when the ground is not frozen, in a hole in the ground, or in a pot. For a bareroot rose take care to spread its roots out evenly in the planting hole before covering them with soil. Firm the soil around the stem and water thoroughly around the base of the plant. Watch for signs of life to reassure yourself that the rose has come out of dormancy and started to grow.

Spring · Outdoors

Apply an organic mulch

Apply a 5-10cm layer of organic mulch around the plant in spring to reduce weeds, retain moisture and keep roots cool in summer. Leave a 10cm gap between the stem and the mulch to prevent stem rot. Before applying mulch, clear the area of weeds and water if it hasn't rained recently. Use biodegradable material such as garden compost, well-rotted manure, leaf mould or bark chippings as mulch.

A mulch is a covering that can: protect the soil surface from rain, heat and cold; deter weeds; provide nutrients. Organic indicates that material has vegetative origin e.g. manure, compost. Synthetics i.e. plastics, or stones are often called mulches.

Spring,Summer · Outdoors

Feed with slow release fertiliser for roses

Apply a slow release fertiliser for roses before applying any mulch, spreading it around the root area of the plant as it is coming into growth in spring. Avoid getting fertiliser on the stem or leaves. Repeat the application after the first flush of flowers, usually early summer. Or apply a liquid feed at regular intervals throughout the growing season. Roses in containers need feeding more often than those planted in the ground.

This is a simple way to provide a nutrient boost as a single annual procedure.

Spring-Autumn · Outdoors

Water to keep the soil moist

For best results, this plant needs soil that is always moist. Water deeply and regularly as soon as soil appears dry. Even for established plants in the ground, a dry week can cause problems with some soils. Check plants in pots more often, especially in hot weather. Or install an automatic irrigation system which will do the hard work for you, even when you are away on holiday.

Without regular watering some plants never fully regain their beauty.

Spring-Autumn · Planting

Manage bugs on roses

Aphids like greenfly or blackfly feed on the sap in young stems and leaves of roses. In small numbers aphids are unsightly, a large number can damage a rose's health. Check roses from spring onwards. Remove aphids by brushing them off with your hand, rinsing off with water, or spray the rose with a mild soapy solution. If an outbreak persists, treat with a "rose spray". Prevent aphid infestations by attracting aphid-eaters like birds and ladybirds to your garden.

Summer · Outdoors

Heatwave care for roses in the ground

Roses generally tolerate hot weather and heatwaves, unless soil around their roots dries out below the surface. To check if the soil is dry, stick your finger in the soil to a depth of 5cm. If flowers are wilting or stems drooping, the rose needs watering. Water roses slowly, directly onto the root area around the base. For newly planted roses, water every other day, for established roses, water once or twice a week, giving each rose a deep drink of 5 litres (half a standard watering can). Making a shallow depression in the soil around the stem base is a good way to catch water and stop it running away. To keep soil cool and reduce water evaporation, add a layer of mulch (compost or bark) on top of flower beds, leaving a gap between plant stems and the surrounding mulch to avoid stem rot.

Summer · Outdoors

Heatwave care for roses in pots

Roses in pots are vulnerable to heat and drying out during hot weather and heatwaves. Check them daily in very hot weather and water in the morning and evening if necessary. Water each pot until water comes out the bottom. Cool pots down by grouping them together, or moving them to the shade. Avoid planting roses in black containers or pots in full sun. To keep soil cool and reduce water evaporation, add a layer of mulch (compost or bark) on top of the pot, leaving a gap between the rose stem and the surrounding mulch to avoid stem rot.

Summer - late · Planting

Prune rugosa roses

This rose has a single main flush of flowers rather than flowering repeatedly through the season. Prune in late summer after flowering has finished to encourage strong healthy growth next year. Wearing gloves, cut stems with a sharp pair of secateurs. Remove dead, diseased and damaged stems. Also any spindly weaker growth. Check stems are not crossed or rubbing and the centre is not too crowded. This allows air to flow around the plant, which helps prevent pest and disease problems. Prune the longest stems back a little to an outward facing bud. Occasionally take out one or two of the oldest stems to the base.

Summer-Autumn · Planting

Cut off faded rose flowers

"Deadhead" roses (remove faded flowers) once a week to tidy the rose, encourage more new flowers and extend flowering. Snip the stem below the faded flowerhead, just above the first leaves you come to.

Summer-Autumn · Planting

Dealing with rose diseases

Rose leaves that have black, brown or orange spots are showing symptoms of fungal disease, while leaves, stems and some flower buds with fine grey or white powder indicate powdery mildew. Don't worry, it's unlikely disease will kill the rose. The remedy is to cut off affected areas where possible and apply a "rose spray" that treats fungal rose disease (most rose sprays treat multiple diseases, check the label). Rose diseases and mildew are caused by airborne fungi, such as blackspot and rust, so burn the diseased rose parts that you cut off to prevent fungi spreading (don't compost diseased rose leaves).

Outdoor planting · Planting

Add root growth stimulant to the planting hole

Mycorrhizal fungi helps roots establish quickly, so they absorb water and nutrients more efficiently. It comes as a powder, granule or gel. Add to the planting hole or container, and to the plant's rootball before planting in the hole. For "bareroot" plants use a gel.

Compost · Planting

Compost for roses

Use rose compost when planting in pots, or add compost as a soil improver when planting in the ground. Rose compost is formulated to provide the ideal nutrients and composition for roses. If you are using peat-free compost, it's important to feed regularly during the growing season using a slow release fertiliser, or liquid feed, as the compost loses its nutrients over time. Roses in pots need feeding more often than those planted in the ground.

Planting roses · Planting

Planting roses in the ground

A rose planted in the ground will typically grow larger and more healthily than one in a pot and will need less watering and feeding. Before planting, soak the rose in the pot it was supplied in by submerging the pot in a bucket of water until air bubbles stop rising. Plant the rose in a hole in the ground so that the soil reaches the same level on the rose's stem as it was in the pot. For best results add a handful of compost or manure, plus a sprinkle of mycorrhizal fungi powder to the bottom of the planting hole before adding the rose. Fill gaps around the rootball with soil, firm the soil, then water thoroughly around the stem to settle the soil and remove air gaps. Ideally position the hole 20cm away from any fence or wall, centrally in your chosen space, making the hole 5-10cm wider and deeper than the pot. When removing the rose from the pot, gently loosen outer roots from the rootball with your fingers. After planting, create a shallow basin around the planted rose to catch water, and water the rose regularly for the first year while its root system is developing.

Planting roses · Planting

Planting roses in pots

A rose planted in a container (pot) will need more watering and feeding than a rose planted in the ground. Before planting, soak the rose in the pot it was supplied in by submerging the pot in a bucket of water until air bubbles stop rising. Make sure the container to plant in is at least twice the volume of the pot the rose was supplied in and has drainage holes in the bottom. Add shingle or small rocks to the bottom of the container, then some compost, add the rose and fill gaps at the sides with compost leaving 3cm between the soil level and top of the container for easier watering. Firm the soil and water the pot well.

Companion planting · Planting

Companion planting for roses

Plant "companion" plants close to roses to support growing conditions, attract beneficial insects and pollinators, while helping to reduce disease and repel pests. For example alliums, catmint, lavender, geraniums and marigolds.