• Tolerate the presence of some thrips damage
• When storing corms from affected plants cut down and dispose of the top growth (preferably in council green waste) before the corm is fully dried to decrease the number of overwintering thrips, reducing the likelihood of a problem in the following season
• Encourage natural enemies in gardens, for example the predatory bug Orius laevigatus can occur naturally   

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Biological control suppliers (pdf document)

Adult gladiolus thrips are 2 mm in length, brownish-black and have narrow, elongate bodies. Adults can lay up to 100 eggs at a rate of one or two per day. These are often deposited on the younger leaves or in flower buds of host plants. The immature stages, nymphs, are pale yellow. There are three nymphal stages (instars). 

The first two stages, like the adults, feed by sucking sap and are entirely wingless. ‘Wing buds’ develop on the third stage which does not feed and is known as a pre-pupal stage. The pre-pupal and pupal stages take place in the soil and in sheltered places on the host plant. Wings are not fully formed until the adult thrips emerge. 

Gladiolus thrips usually has two or three generations a year but may have more during hot summers. The thrips overwinter concealed on stored corms and can even continue to reproduce as long as the temperature remains above 10°C (50°F).