Alan's Monthly Garden Calendar - June; Ornamental Garden Tips

Published on June 9th 2019
June is one of the most beautiful months to be in the garden, and I plan to be in mine every hour that I can. Growth is reaching a peak, and some plants will need to be supported and a few pruned. There are some timely sowing and an opportunity to plant more tender plants too. Check my weekly tips for more tips not covered here and of course, read my June tips on growing edibles as well.

Pots and borders

  • Plant up hanging baskets and containers for colour and scent all summer.
  • Winter flowering pansies and spring flowering wallflowers should be replaced with summer flowering bedding plants now. They may still have some blooms, but they will quickly look scruffy.
  • Lift and divide clumps of primroses and polyanthus. Heel them in a shady place for summer, and they can be replanted in your borders again in autumn.
  • Continue planting out summer flowering bedding plants. Long flowering traditional ones like Pelargonium, Petunia and Begonia are hard to beat!
  • Lift, dry off and store tulip bulbs in the shed or garage ready to replant in late autumn.
Brompton stocks flower in a garden
  • Sow wallflower, brompton stock and sweet william seeds in drills outside for planting out in the autumn.
  • Raise your border perennials by sowing several popular varieties now. Sow Delphinium, hollyhocks, lupins and foxgloves. Keeping them cool will help germination at this time of year. These will flower next year.
a hollyhock flower
  • Stake tall plants to give them support.

Pond and bog plants

  • Oxygenating weeds in ponds may be getting out of hand now so thin them a little. Put the plant material on the pond edge for a few hours, as this allows many water critters time to crawl back into the water. Always try to leave at least a third of the water surface covered to provide shade and shelter for wildlife.
Beth Chatto pond with boat and water lilies
  • Plant water lilies and other water plants this month. Use a pond plant container filled with soil without added peat, bark coir etc. Cover the surface of the soil with gravel to stop it dirtying with the water.
  • Make sure that water margin and bog plants are getting enough water and add mulch to help.
    {"type": "download_cta", "text": "Download the free Candide App to get help and answers from a warm community of gardeners"}

Lawns, hedges, paths and drives

A green garden lawn
  • Don't be tempted to cut your lawn too low! Raising the blades slightly now will give a harder wearing surface which resists dry periods better. Mow a little and often.
  • Control clover, trefoils and black medick Medicago lupulina in lawns. Weedol Lawn Weedkiller is probably the most effective weed killer currently available, but several applications might be needed for these tough to control weeds.
  • Pep up your lawn with a high nitrogen summer feed. Westland After-Cut works very well, but there are others on the market, including those you can water on.

Weed control

hoeing weeds in a garden
  • Regular hoeing, especially during dry weather, will keep weeds under control and stop all but the most determined perennial weeds from getting established.
  • Persistent perennial weeds should be treated with Resolva 24H or Roundup now. Tough weeds like couch grass, creeping thistles, creeping buttercup and bindweed may need several applications. If the weeds are in among plants that you wish to keep, carefully use Roundup Weed Killer Gel. Don't be tempted to cut them back before application, because the lusher the leaves are, the more likely you will get a good result.
  • Control ground elder and horsetail with glyphosate-based weed killers. You will need several applications to kill it. Bruising the weed a little and adding a few drops of washing up liquid to the spray improves results.

Trees, shrubs and climbers

A close up of a clematis flower garden
  • New shoots on any climbers, Clematis in particular, should be tied to supports to prevent them from breaking. Old, early flowering Clematis can be cut back hard if needed, and this will rejuvenate them.
  • Remove dead flower heads from roses regularly, as this encourages more blooms.
  • If Magnolias have got too large, they can be pruned this month, but only if you have to.
hazel stick perennial plant supports in a garden
  • Floppy border plants may need support to prevent them from falling all over the place. There are lots of devices on the market to help with this, or you may prefer to make your own with natural materials.
  • Make sure that newly planted trees and shrubs are getting enough water and that it is reaching the roots! Trees need a minimum of two gallons a week.
Box hedge and bay laurel topiary garden
  • Box hedging and topiary are best trimmed now. Mix the clippings with grass from your lawn as this will improve the compost you make. There is some evidence that if you don't tidy up your box, it may be more prone to box blight so try to pick up all the trimmings that you can.
Free download for your phone or tablet
Download on the App StoreGet it on Google Play

Lots to see

Making plans to stay local or explore a new area? Use the Places map to explore and find out more details of gardens around your current location. To find gardens and garden centres near you download our free app.
Download on the App StoreGet it on Google Play