June

June - The garden should be full of colour this month with vibrant displays of flowers in your borders and tubs. You should also be able to start harvesting vegetable crops.

Flowers

• Sprinkle feed around roses
• Divide congested flag iris
• Stake tall lilies in pots
• Cut back pulmonarias and doronicum, invasive alpines and ground cover
• Divide primulas
• Trim oriental poppy growth at the base once flowers fade
• Look for aphids on lupins and spray them with soapy water
• Cut away spring bulb foliage once it dies back in late June
• Position summer hanging baskets and containers outside
• Plant out summer bedding

Tip: Be ruthless with roses

To ensure a succession of flowers throughout the summer, deadhead your rose bushes regularly. Remove individual flowers as they fade and once they have all finished, prune the whole head back to the first leaf that you come to. A new shoot will strike put here, bearing another flower that will bloom in late summer. Delay deadheading and you will impede the plants second flush.  

In the greenhouse

• Water crops in pots and grow bags regularly
• Pot on seedlings, begonias, gloxinias and rooted cuttings
• Cut off faded flowers
• Repot houseplants
• Damp down the greenhouse floor every morning to increase humidity
• Take cuttings of fuchsias, pelargoniums, verbenas, osteospermums, hydrangeas and penstemons
• Shade greenhouses to keep them cool and prevent scorch

Tip: Train your tomatoes

Greenhouse tomatoes should be trained to be a single-stem. Pinch of side-shoots so energy isn’t wasted on unwanted growth and check frequently as second stems can form in no time. Tomato fruits are self-fertile but to ensure food pollination and the setting of fruit, gently tap the flower trusses, or brush them with a feather, as they form. We have great expectations of our tomato plants, so apply fertiliser on a weekly basis to help them along. 

Fruit and vegetables

• Plant out marrows, squashes, pumpkins, and sweet corn
• Thin our seedlings to their required spacing
• Hand weed between crops
• Tie in new fruit canes to supports
• Cover strawberries and ripening berries with netting
• Crops to grow outside now are lettuce, endives, carrots, runner beans, French beans, cauliflowers, peas and sweet corn
• Watch out for woolly aphid on fruit trees – spray them off with soapy water
• Harvest lettuce, radish, other salads and early potatoes

Tip: Sow salad!

Short on space – you could sow a pot of salad leaves. Simply fill a large flower pot with compost and sow a few lettuce leaves into it. Choose a cut-and-come-again loose leaf variety rather than varieties that form large heads. You can then pick the leaves every week and the plants will continue cropping for months.

Around the garden

• Prune broom after flowering
• Repot houseplants
• Rub off any greenfly you find
• Hoe borders to keep down weeds
• Water hydrangeas with colorant to keep them blue
• Treat gravel drives and paths with weed killer
• Boost border growth by giving plants a liquid feed
• Take cuttings of pinks
• Continue spreading mulches around shrubs and trees
• Feed lawns and treat any moss and weeds
• Add water-retaining gel and slow-release feed to compost in patio post and hanging baskets
• Cut the lawn – at least once a week
• Use rainwater collected in water butts

Tip: Beware of brambles!

Brambles are amazing invaders. Wearing thick gloves follow the tendrils of brambles back to their point of origin. It is pointless just cutting the shoots as they will soon grow back stronger than ever. You really need to dig out the roots. Don’t ignore brambles, every time a new shoot touches the ground it will root and develop a new plant, making the problem worse.