Answer: Earthworms do not feed on plant roots, but instead digest soil. I think what you found was a coincidence. Earthworms in the soil are an indication that you have moist, loamy soil - that's a good thing. As for having your newly planted flowers die, I suspect they were wilting due to transplant shock and if you water them deeply every 3-4 days, they should perk up. Sometimes plants are in protected places in nurseries and when you take them home and plant them where they are suddenly exposed to hot sunshine, they can really wilt and look awful. One way to combat that is to plant them, water them well, then set a temporary shade cloth up until the plants become established. This will help them cope with being planted during the summer time.
Best wishes with your garden!
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