Spring weather is a boon for garden pests, many of which have been inactive in the previous cool months. Some like the psyllids that attack Eugenia hedges or eucalyptus trees appear before their natural predators make their seasonal comeback. Be patient while waiting for their enemies to reduce psyllid populations and the damage they do. Eugenia hedges can be sheared every 6 weeks to remove new foliage damaged by the Eugenia psyllid. Leave the clippings around the base of the plant to allow time for tiny beneficial wasps that attack psyllid larvae to emerge. Do not feed plants with nitrogen fertilizer in spring since lush, new growth favors psyllids.