Break open a bud and you will see a small, yellowy larva inside the hollow stem; spray Toppel 10, Dursban WG or Gyro. The aim is to control either the adults during egg laying or the young larvae during hatching. Good needle and stem coverage is essential so use high water rates and a wetting agent.
Rust - Keep a watchful eye and check the underside of the older foliage of Hypericum, Mahonia, hollyhock, Vinca, Salix and roses for rust. Spray with Nimrod, Amistar or Systhane 20EW when seen.
Pines - Pine shoot moths are now active; look out for gumming around the buds and stunted leader growth.
Camellia - Now is the time to apply Cycocel to camellias for sale next spring; the rate is 3,000ppm - continue with liquid feeding for this month only.
Eelworm - Tell-tale angular patches on the lower, older leaves of Weigela, Philadelphus and Buddleja usually mean the presence of leaf and stem eelworm. Do not take cuttings from these plants. Vydate 10G applications will reduce the levels of infection from the pest but render the plant unsaleable for six weeks. An off-label approval is required for use in ornamental plant production (1993-0020).
Heaters - Use this summer time to have your heaters serviced and made ready for use in the late autumn. Get the job out of the way so that you do not have a panic when the frosts start.
Algae in reservoirs - A number of products are available to clean up algal growth in reservoirs. As well as the barley straw (recommendations are 15-25g/sq m in spring and autumn), there are products containing beneficial micro-organisms like Lake Relief from Novozymes or Algae Pro from Oxyjet.
Flea beetle - A number of plants are vulnerable to this pest which can cause significant leaf damage and render plants unsaleable. Apply Decis now to plants outside.
Weed control - Contact-action products like Shark (SOLA 2008-0552) or Reglone can control a range of young, annual, broad-leaved weeds on non-crop areas on the nursery. With scrub and weedy areas in full growth now is a good time to apply Roundup to them. The uptake is quick and the control more effective at the moment. A second application six weeks after the first is usually sufficient for total control.
John Adlam is the managing director of Dove Associates