As the summer season draws to a close, what should we cut back? Is this everything or a particular plant that may benefit from a prune. Plants that flower off last years growth such as Forsythia, it’s good practice to cut back immediately after flowering not only to curb them becoming invasive but it can affect next years flowering.
Rose of Sharon – (Hypericum calycimum) – this particularly invasive perennial needs to be cut to the base and any unwanted growth removed. It is a part of the Hibiscus family but this common one should be treated as a weed, however lovely the yellow flowers appear. If it is starting to encroach on neighbouring plants, it is worth digging some of out to reduce its size and control its growth. It will come back so a case of managing this.
What is necessary to do is to cut the herbaceous perennials down and start removing the dead growth around them. This housekeeping is important to remove dead growth, apply protection like mulch if it needs it, reduce disease and prevent pests sheltering over the winter. These plants go to sleep underground and above the surface appear dead or dormant.
Russian sage – (Perovskia atripicifolia) – this perennial is so easy to look after. It is drought tolerant, attracts beneficial insects and has a beautiful fragrance. So simple to cut back. A similar perennial is Nepeta. It has the same sort of habit. Marginally lighter purple. It is very low maintenance and once in situ withstands neglect.
Catmint (Nepeta) A perennial that likes sun. It’s long flowering so may be still in bloom. It is low maintenance and only requires cutting back. Do this shortly after flowering but reshape, don’t cut it right back.
Coral Bells – (Heuchera) (Forever purple) or green foliage (Delta dawn). This is great for filling in a gap although do make sure the soil is free draining. They do not sit well in water. A clump forming perennial offering yellow flowers through the course of late spring to early summer. Cut off spent dead growth and expose young shoots.
Hollyhocks – (Alcea) – A hardy perennial that needs full sun. It is important to have rich moist soil too. Pull the canes out and cut to the base. High winds will only break the stem and all the goodness has gone to the ground. Hollyhocks lifespan can be extended by cutting it down immediately after flowering or they can regenerate themselves and self seed too.
Delphiniums are hardy specimens, easy to grow, but not so much in poor soil. A reliable summer flowering perennial. The position needs to be a little sheltered and the soil needs to be fertile. With Delphiniums we can achieve a bold statement of purple, blues, lilacs and whites. Delphiniums do need full sun so worth remembering not for a chilly corner either
Bergamot (Monarda) can be cut down and dead growth removed. A summer flowering perennial. It is hardy offering a scented fragrance from its leaves. It is drought tolerant and will perform in light shade.
Crocosmia/Monbretia – These perennials are clump forming and can become invasive. These perennials however will perform in any kind of soil, any aspect, any consistency. They procreate on their own so pulling a few rogue ones out will do any harm. These perennials are very hardy. There is no difference in the name – Monbretia is more traditional.
Woody shrubs to treat now, the following or left until spring. They require a little more of an explanation so “shrubs” will follow this.
Spirea – mound forming shrub in summer. Cut back to a neat shape to encourage new growth in spring. These shrubs prefer full sun but can tolerate some shade.
The flowering currant (Ribes Sanguineum) A spring – summer flowering shrub, which is accepting of most aspects. The soil needs to be water retentive but still free draining. It will benefit from nutrients in spring but quite tolerant of poor soils. It is important to take away superfluous growth but not all to encourage new growth. A good practice is to thin out crossing branches and leave a number of thick central stems. Cut to a leaf node and tidy.
The Butterfly Bush (Buddleia) and (Hydrangeas) certainly needs pruning but these can be left until spring. Over winter some argue that it helps protect the plant underneath. I don’t think it’s terribly important, If it doesn’t look un aesthetic in appearance, just leave. The important factor is that they are cut back. It regenerates growth and prevents them from becoming woody. Hibiscus too, although I tend to leave until spring. Although these woody shrubs will re generate from a prune. Leave these until spring.
Roses too can be cut down now- any dead, diseased and damaged stems if flowering has finished (although if you dead head you may still have flowers) in preparation for winter. In the event these are untouched shortly before adverse conditions leave until the spring. One or the other but not in between. Roses don’t need to be cut entirely but dead head and start to thin them out. A good practice to cut them a little more in spring and remove any stems haven’t regenerated after the adverse weather.