Pot-toppers Pot-topping is becoming more popular because a smaller range of herbicides is available for protected crops. Bark-topping machinery that will automate the task is available and increasingly in use. Other products have been developed including crushed glass, coir mats, Biotop and cocoa shells, as well as polythene slips, grit and shredded Miscanthus. The effectiveness of these products depends on the time that the crop is present on the nursery, your watering regime and weed pressure from the surrounding area.
Weed control This is the best time to apply Roundup to perennial weeds. As the plant dies down for the winter the glyphosate is taken into the plant; it continues to remain at a low level of activity all winter and suppresses re-growth next season, giving you a head-start on the weeds. Where you have patches of mare's tail, I have found that glufosinate-ammonium seems to be consistently the best control product for rapid knockdown. If you use Roundup make sure you bruise the stems first and add Codacide oil, as it aids uptake and improves control. You will need several applications to get good control.
New container beds Legislation in the long term will look more closely at the water discharged from drains, so if you are planning new beds remember to include water recycling in the scheme. That will help you in controlling any contaminating discharges from your site.
Residual pests The following pests are still active in tunnels and glasshouses: whitefly, Western flower thrips, aphid, two-spotted spider mite, leaf hopper, leaf miner, mealy bug, vine weevil larvae and slugs/snails. As the temperature falls, particularly at night, Aphidius and Encarsia become less active, so chemical means of control become more necessary. If you intend to continue applying Amblyseius for thrips control through the winter, use products such as Chess WG (SOLA 2008-2834), Aphox, SB Plant Invigorator, Majestik or Dynamec.
Mites Apply Apollo 50SC to outdoor trees and shrubs with known spider mite problems as this will reduce the overwintering egg population. October is the peak for Aster lower-bud malformation, so include these and Picea albertiana 'Conica' in the Apollo 50SC programme because conifer spinning mite overwinters as an egg too. On warm days it is possible to see rust mites on ash and Malus buds. Spray with bifenthrin, chlorpyrifos or Sequel to reduce the overwintering population.