Answer: Shasta daisies normally produce dozens and dozens of flowering stems all summer long so there's obviously something amiss with yours! Shastas grow best in full sunshine and well amended soils (which helps retain moisture). If your plants look healthy but are producing few flowers, the problem might be thrips. Thrips are small, winged insects that attack many types of plants and thrive in hot, dry conditions). They can multiply quickly as a female can lay up to 300 eggs in her life span of 45 days without mating. Most of the damage to plants is caused by the young larvae which feed on tender leaf and flower tissue. This leads to distorted growth, injured flower petals and premature flower drop. Thrips also can transmit many harmful plant viruses.
To prevent and control, trap with yellow sticky cards or take advantage of natural enemies such as predatory mites. Sometimes a good steady shower of water will wash them off the plant. This winter be sure to remove all debris from your plants after frost kills the tops down. Consult your local garden center professional or county Cooperative extension office for legal chemical recommendations.
Hope this information helps.
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