Caroline,

Thank you for your question.

Could you take 3 photos: 1 far away so we can see the site, one of the plant and one close-up of a flower and a leaf?

Do you know the type of hydrangea?

Different types of hydrangea are sensitive to time of year when they were  cut-back.

3 years ago you cut it back deeply. Can you describe when you last trimmed it (key information), which month? And how long you left the stems?

Caroline,

I have these question and have filled out the answers you previously gave:

1. When did you prune it in the last 1 year? "Pruned 3 Y ago, and none in last 2 years"

2. Winter Injury this past year in Michigan, Did you area suffer from deeply cold temperatures last winter? 

3. Any evidence of deer eating the plant? Are deer prevalent in your area?

4. How do you fertilize? 

Photo of elements balance on package and pH? 

Any bio fertization? "Grass clippings"  how often?

5. Late freeze in your area? especially when it got warm for a while in early Spring promoting growth, then it got cold again IE 2023 as happened in Michigan this Spring.

6. Describe light it receives in the morning and

the late afternoon?

7. Type of Hydrangea?
How did you recieve the hydrangea? An Easter or Mother’s day gift?

If from a  garden source, when does it normally bloom?

Blooms mid- to late summer (these  produce flower buds in spring.)  it is likely a 

smooth hydrangea (Hydrangea arborescens) or panicle hydrangea (Hydrangea paniculata) 

Blooms in spring and early summer (these formed buds the previous summer or fall).) are likely:

bigleaf hydrangea (Hydrangea macrophylla) or oakleaf hydrangeas (Hydrangea quercifolia). 

Caroline,

Thank you for your question!

When hydrangea fail to bloom there are several possible causes. Considering the pattern of leaves everywhere, but flowers only low on the plant, and you did not mention leaf dammage from chewing injury (Deer) the most likely cause this year is:Winter InjuryOakleaf and bigleaf hydrangeas form flower buds in late summer and fall for the following spring.Also, Buds below the ‘snow line’ on a flowering shrub is a good sign of winter kill of the buds on the exposed parts of branches. Flower buds are typically more sensitive to cold than leaf buds, so you get leaves on exposed branches but not always flowers. ( forsythia is often affected this way, too).

Addressing all of these will likely produce the results you want in the future.
1. determining what type of hydrangea you are growing. Here’s a trick: if your hydrangea does not bloom in spring, instead it blooms exclusively in mid- to late summer, it is likely a smooth hydrangea (Hydrangea arborescens) or panicle hydrangea (Hydrangea paniculata) and it produces flower buds in spring. Because smooth and panicle hydrangeas develop flower buds and bloom all in the same growing season, they can be pruned in very early spring.
Hydrangeas that bloom in spring and early summer are likely bigleaf hydrangea (Hydrangea macrophylla) or oakleaf hydrangeas (Hydrangea quercifolia). These hydrangeas bloom from flower buds that formed the previous summer or fall. The best time to prune bigleaf and oakleaf hydrangeas is early summer, right after they finish blooming.
What to do: Prune your hydrangea at the right time and you’ll avoid cutting away flower buds. If you do make a pruning mistake, let the plant bounce back and bloom the following season before doing any more pruning.2. Winter InjuryOakleaf and bigleaf hydrangeas form flower buds in late summer and fall for the following spring.Also, Buds below the ‘snow line’ on a flowering shrub is a good sign of winter kill of the buds on the exposed parts of branches. Flower buds are typically more sensitive to cold than leaf buds, so you get leaves on exposed branches but not always flowers. ( forsythia is often affected this way, too).3. Deer DamageTender stems and fleshy buds will serve as a welcome snack for deer. Hydrangeas are commonly browsed by deer year-round. Winter browsing will eliminate flower buds on oakleaf and bigleaf hydrangeas, while browsing during the growing season will strip away the flower buds of panicle and smooth hydrangeas.4. Too Much NitrogenNitrogen fertilizer promotes deep green leaves but few flowers. Avoid fertilizing your hydrangea with a high nitrogen fertilizer. If you don’t fertilize your hydrangea, it can still be affected by excessive nitrogen because of nearby turf. Lawn fertilizer is often high in nitrogen and can wash into the soil around hydrangeas.What to do: When fertilizing hydrangeas, choose a product that is high in phosphorus rather than nitrogen to encourage flower production.5. Late FreezeA late freeze in spring can kill developing flower buds. Hydrangeas are especially susceptible to a late freeze if the preceding growing days have been mild and the hydrangea is actively growing.What to do: Pay close attention to the weather forecast in spring. If a late freeze is predicted, protect your plants from frost with sheets or blankets. Use brick, rocks, or anything heavy to secure the cover to the ground.6. Not Enough LightHydrangeas grow best when they receive bright morning light and part shade in the afternoon. Plants growing in too much shade will have few flowers and elongated, floppy stems.What to do: Move a hydrangea planted in too much shade to a brighter growing location. The best time to transplant a hydrangea is early spring.

Here is an easy-to-read academic webpage: https://extension.psu.edu/why-doesnt-my-hydrangea-bloom