Posted on 10-6-2025 by info_virtual-efficiency.nl
Gardening in June - pruning, attracting butterflies and summer garden care
Although summer officially begins after the longest day (21 June), early June can already feel quite summery when the sun is out. The borders are full of colour thanks to flowering perennials, roses, and the first annuals. There’s plenty to enjoy—and plenty to do. Cut back perennials, trim hedges and spring-flowering shrubs, and attract more insects by planting for butterflies. It’s a lovely time to spend a full day in the garden.
Cut back perennials
Many perennials that have finished flowering this month can bloom again if you cut them back. For early bloomers like catmint (Nepeta), trim all spent flower stems before the end of June—new blooms often appear shortly after. Summer-flowering perennials can be cut to delay blooming and make them sturdier, a technique known as the ‘Chelsea chop’. From late May until 21 June, cut back the whole plant by one third to one half. This keeps them shorter and stronger, and they’ll flower about four weeks later. Alternatively, just cut half the stems—some will flower at the usual time, others a few weeks later. Great for phlox, sneezeweed (Helenium), and Joe Pye weed (Eupatorium).
Pruning spring-flowering shrubs
Shrubs that bloom early in spring should be pruned in June, right after flowering. This applies to all varieties that bloom before the longest day, such as redcurrant (Ribes), forsythia, magnolia, broom (Cytisus), deutzia, serviceberry (Amelanchier), lilac (Syringa), Japanese kerria (Kerria), mock orange (Philadelphus), and Weigela. These shrubs produce flower buds on old wood—branches from the previous year that developed buds last summer. Cut back all spent flowering stems, ideally just above a new shoot, and maintain a balanced shape. Pruning helps keep shrubs compact and blooming abundantly. If left unpruned, they can become bare at the base and only flower at the top—commonly seen with lilacs.
Tip: Trim hedges
To keep hedges and topiary dense, trim them before the longest day (21 June). Most shrubs produce another flush of growth after midsummer, which fills in any bare patches. Trim hedges with a slight taper—wider at the base than at the top—so they receive plenty of light. Don’t forget to fertilise after trimming with a special hedge feed.
Butterflies in the garden
Unfortunately, butterfly populations are struggling in many areas. While gardens can’t replace natural habitats, they can support around twenty butterfly species. The simplest way to attract butterflies is to plant nectar-rich flowers. Most have stunning blooms, so it’s no hardship to grow them. Choose a mix that provides nectar from spring to autumn—from April to October. Early bloomers like Aubrieta, honesty (Lunaria), and dame’s rocket (Hesperis) are ideal, while late-summer options include sedum (Sedum), blazing star (Liatris), and autumn asters.
Top 10 butterfly plants
- Autumn aster (Aster novi-belgii)
- Butterfly bush (Buddleja)
- Purple coneflower (Echinacea)
- Globe thistle (Echinops)
- Dame’s rocket (Hesperis)
- Lavender (Lavandula)
- Marjoram (Origanum)
- Phlox
- Stonecrop (Sedum)
- Vervain (Verbena)
June bloomers in the spotlight
- Yarrow – Achillea millefolium
- Delphinium – Delphinium
- Foxglove – Digitalis
- Hardy geranium – Geranium
- Daylily – Hemerocallis
- Coral bells – Heuchera
- Catmint – Nepeta species
- Lupin – Lupinus cultivars
- Roses – Rosa
June garden tasks
Planting and sowing
- You can still plant summer-flowering annuals in pots or borders
- Sow biennials (June–July)
Pruning, trimming and staking
- Prune spring-flowering shrubs after blooming
- Trim hedges before mid-June
- Cut back perennials before the longest day
- Deadhead faded blooms to encourage reblooming, especially on roses
- Provide extra support for tall plants if needed
Feeding and mulching
- Add mulch and hedge fertiliser after trimming
- Feed annual summer flowers regularly via the watering can
Other tips
- Water during dry spells, especially new plants
- Keep on top of weeding
- Water container plants generously
- Prepare your garden for your holiday: weed, trim, stake and ensure watering (set up sprinklers or ask a neighbour)
Text: Modeste Herwig.
