June Gardening Tips

  • 03 min read
  • 31 May 2023
June Gardening Tips


Mulches help to conserve water but the soil must be moist before they are applied.

Sow quick growing hardy annuals e.g. clarkia, Virginia stocks for late colour in dull


When watering concentrate on climbers on walls, container and basket plants, newly

planted items, dahlias, sweet peas, leafy veg. crops, celery and fruit bushes.

Dig up bare centred alpine plants and divide them, re-planting the young pieces from

around the edge.

If you use nematodes to control vine weevil grubs buy them on line or mail order.

June is one of the worst months for pest and disease attacks, so check plants

regularly. If using a trigger spray product remember to shake it first and there are

lots of safer “organic” treatments available now.


Make sure plants in tubs and baskets are fed regularly, as well as watered.

Many climbing plants can be increased by layering at this time of year.

Mow the lawn to leave the grass 2.5cm (1in) tall. Makes grass more drought


Treat established lawns with a lawn weed killer but not if there is a drought.

Dead head rhododendrons after flowering to encourage new growth.

If you need more fish in your pond this is an ideal time to introduce them but

goldfish can be detrimental in a wildlife pond..

When picking strawberries always remove any rotting fruit, otherwise problems


Watch out for cabbage white butterflies around your brassica plants. If you do not

like to use chemical sprays try Grazers G3 organic caterpillar repellent. They also

make good repellents for slugs and lily beetles too.

Sow radicchio now for winter salads. Choose a good coloured variety like pallo rossa.

Sow salad crops regularly, in small amounts, sowing the second row as the first


Tomatoes can be planted outdoors. Select a sheltered site and support the plants.

Take cuttings from dianthus (pinks). They root easily now in a shady spot.

Lettuce will not germinate in hot weather. Sowing in moist drills in late evening helps


Shade the greenhouse, ventilate it well and spray water over the floor to raise


Take softwood cuttings from shrubs. Remove 7.5 cm (3in) of shoot tips. Root in pots of gritty compost, placed in polythene bags, in a shady spot.


Lift and divide flag iris after flowering. Re-plant young growths, keeping rhizomes

above soil level.

Prune back side shoots on cytissus (broom) after flowering to keep plants neat.

Deadhead roses regularly to prolong flowering. Remove any “suckers” as soon as

they appear.

Watch out for algae and blanketweed in pools. The introduction of a product based

on barley straw can provide an organic control measure


Feed tomato plants regularly from when first fruits begin to form, using tomato food.

Take out one third of the older branches on deciduous shrubs, like Philadelphus, Weigela and Deutzia after flowering.

Put cymbidium orchids outside in a sheltered, shady spot until late autumn. Keep them well watered and fed over this period.

If pollen beetles infest your cut sweet peas, put them in water in a shed for a while.

The beetles will fly into the window attracted by the light.