Bacterial infections: Ensure you have sprayed Croptex Fungex on peaches to control peach leaf curl and include plums, damsons and greengages if you experienced pocket plums last year.
Don't forget to include ornamental Prunus species and apply the product after wet weather to control the bacterial leaf spot that is the cause of shot-hole. Try to avoid overhead irrigation for 24 hours after spraying to give the product time to work and stick to the leaf surface as it can be easily washed off straight after application.
Spider mites: Mite eggs are starting to change colour from red to orange so the maximum effect of Apollo 50SC to reduce the mite population will be gained by applying it now. Two-spotted mites overwinter as adults and Apollo 50SC has little effect on them. Use SOLA 2001-2268 for application over protected crops.
Aphids: Remember to check conifers for aphids. Brown and green aphids are now widespread but hard to spot with a quick glance. They are usually close to the main stems and merge well with their surroundings. Use contact products and high water rates to penetrate the plant canopy.
Root rots in propagation: Keeping the damping-off diseases under control on seedling material is important right now. Products such as Filex and Basilex on some species are helpful in reducing disease levels. Ensure moisture levels and air temperatures are not too high and adequate ventilation is available to reduce the need for heavy pesticides.
Gleditsia pea gall: Timing of pesticide applications is the key to successful control of this disfiguring pest. Spraying the emerging leaflets in spring was found in the US to be the most effective. Use products such as Gazelle, Admire or Hallmark WZT.
Choisya: I find that many growers struggle with stem and root rotting on this genus. In many cases it can be identified as a fungal infection such as Pythium. I do think, however, that timing along with good growing-media water management has a big part to play in successful Choisya production. Potting them earlier, between March and April, and watering with care does seem to allow better root establishment and a stronger plant that resists root fungal attacks.
Scale insects: Remember to check bay trees, Hedera, citrus and Camellia. Spray with Savona or Chess WG at the SOLA rate (IPM) or Decis, Decis Protech or Certis Spraying Oil (non-IPM).