- Pinch out side shoots of tomatoes to increase yields and keep feeding with tomato feed.
- Feed roses to keep them flowering strongly.
- Pot up houseplants that have become top heavy or pot bound.
- Be on the lookout for developing pest problems and take action.
- Cut down delphiniums once flower spikes fade.
- Treat weeds with a lawn weed killer before they get a firm foothold.
- Sow seeds of herbs, including basil, parsley and coriander.
- Bury shoot tips of blackberries and peg them down to raise new plants.
- Keep an eye on your greenhouse or tunnel with this ever changing weather we are having. Ventilate daily and add extra shading if temperatures get too high.
- Cut back pansies that look straggly to encourage new growth.
- Shorten half the shoots on broom and genista to encourage new growth.
- Thin heavy fruit crops, picking off the smallest. Aim to leave developing fruits about 10-15cm apart along the stems, perhaps thinning congested spurs down to just a single fruit.
- Trim conifers and other garden hedges.
- Spray apples and gooseberries with a fungicide to protect against mildew.
- If you are away on holidays from your greenhouse for a few days Stand pot plants on capillary matting and hang up sticky yellow traps to catch whitefly and flying insects.
Following on from last week’s article on hydrangeas, I will now introduce the more unusual varieties like Hydrangea arborescens Annabelle which produces an abundance of round white fluffy flowers from mid-summer onwards. Best grown in a large pot or at the back of a shrub or herbaceous border as it can reach up to 1.5 meters (4-5ft). There is a pink variety called pink invincible Annabelle which is also well worth planting. Another variety well worth seeking out is Hydrangea Aspera Sargentiana which grows into a large shrub up to 2 meters high, its distinctive magnificent fuzzy, blue-green leaves is smothered from late summer onwards with a white lacecap type of bloom which spans 8 inches across. The dome shaped bloom will have florescent purple fertile flowers that radiate colour in the summer. This is a very unique hydrangea and a must have for the serious collector. Sargentiana can serve as an outstanding backdrop for other blooming hydrangeas, leave it some room and it won't disappoint. One of the best plants for brightening up a north facing dark wall is Hydrangea petiolaris, it will succeed and thrive in such an aspect where most other climbers struggle. Hydrangea petiolaris is a free flowering variety producing an abundance of white lace cap flowers. Last but not least is Hydrangea Quercifolia and as the name suggests this Hydrangea has a leaf the same shape as an oak tree leaf, it turns vivid shades of orange, crimson and purple in the Autumn, after producing cream flowers all summer that fade to pink. If you have room for this large shrub which grows 1.8 x 1.5 meters plant one or three! Confused – we’ll deal with feeding and pruning next week.