Escallonia - A reminder for the final application of a magnesium chelate at the rate of 1:200 as an overhead spray with Librel Liquid Mg or Vytel Liquid Magnesium. This can be added to most pesticide sprays as a tank mix. As with all chelate sprays, make sure the weather is cool when you spray the foliage.
Downy mildew - Maintain the control of downy mildew with sprays of Aliette 80 WG, Fubol Gold WG, Filex, Proplant or Subdue. Weather conditions are everything with this disease and trying to dry off the leaf surface once every 24 hours makes all the difference to your control programme.
Spraying windows - With constant showers, spraying can often be difficult. Consider adding products like Celect, which can improve the rain-fast nature of products.
Feeding - Some of the sales this season have not cleared out as many crops as we expected and I have seen a lot more plants being kept in nurseries for longer than planned. The result of this is that the nutrient supplies in the compost may not carry the plants through to the autumn or even next year, especially if a short-term product was used. Check the nutrient status of vulnerable crops and top-dress with Sincron, if required, to maintain plant freshness through the autumn. If you intend to keep plants for next spring then make sure they have CRF plugs added and an appropriate liquid feeding programme in place. Older plants can often be the most neglected in the nursery and become breeding grounds for many weeds, pests and diseases.
Vine weevil - Plants that did not have any vine weevil control in the growing media at the beginning of the season will need a drench in September with Intercept 70 WG or nematodes. Egg-laying will occur at any time now and the larvae start developing around six weeks after that.
Apple scab - Wet weather encourages scab on susceptible species. If you have maintained a routine "top up", continuing that now will keep it at bay. If not, do a full scab spray of both eradicant and preventative products like Dithianon Flowable or Radspor FL. Both these give good eradication of active scab. Remember to include Chaenomeles and Pyracantha in the routine spray as they are susceptible too.
John Adlam is managing director of Dove Associates