Hello, teresa. It sounds like you have a hydrangea macrophylla that blooms on old wood. The leaves in the cages are a form of winter protection for these hydrangeas and it should be discontinued once danger of frost has passed. Your local nursery can advice when the average is for your location (and when to put them back in fall).

Because Mother Nature is in charge of the weather department, I suggest that you add two more weeks to the average. If at any time it looks as if you will be continuing to have an even longer winter, feel free to postpone removing the leaves once again.

If the plants have been placed in a location that supports their size at maturity, there should be no need to prune. When pruning is needed, it should be done after blooming but before the end of July. Flower buds for next spring will begin to be developed sometime in August/September.

Keep the soil moist and the plant mulched with 3-4" of acidic mulch up to the drip line. Fertilize once in June with manure or cottonseed meal. Use lighter fertilizers (like liquid seaweed, coffee grounds, liquid fish, etc) during the growing season as desired but stop at the end of July so the plant goes dormant on time for the start of winter.

If your soil is not acidic (a soil test can tell you; a nearby local nursery can also help; a soil test kit from Lowe's/HD/etc can approximate) then you will need to ammend the soil once a year or so to prevent iron chlorosis. This condition shows up on the leaves when the soil is alkaline. You combat this by adding soil sulphur, aluminum sulfate or by adding liquids containing iron chelated products. When the plant gets iron chlorosis, the leaves turn yellowish, except for the leaf veins. The veins stay a deep dark green color.

If you have trouble watering, use the manual method for a couple of weeks.... insert a finger to a depth of 4" and water only when it feels almost dry or dry. Note the date on a calendar. When the calendar notes indicate some kind of watering pattern is developing (you are watering every 3/4/5 days) then set the sprinkler to water on that frequency. Repeat this if the temperatures fluctuate 10-15 degrees in either direction and stay there. During winter, water only if it is dry and the ground has not frozen (once every two weeks is probably ok).

To prevent fungal infections in the leaves, water the soil and not the leaves. The best time to water is early in the morning. Pick up plant debris under the shrubs and check the mulch once a year. Do not plant other shrubs close to the hydrangeas such that air flow between the plants decreases (this could make either plant get fungal infections).

Hope this helps you,
Luis