Some hydrangea cultivars are more cold-hardy than others. Even though our winters have been comparatively mild overall (and are trending that way longer-term), sometimes we experience a mild period in winter followed closely by a cold snap to near-freezing, which can damage even hardy plants. Plants blooming on old wood (the growth of the prior season), like many hydrangea species, will have flower buds for the following season on their stems lying dormant during autumn and winter. Therefore, even if not prominent, they are vulnerable to cold, drought, deer browsing, and pruning, since the plant cannot replace them in time to flower in spring. It's also fairly common for mophead hydrangeas to start breaking dormancy early, beginning to leaf-out and have buds break open, only to have those same leaves/buds injured or killed by a late frost. While the overall plant survives this and gradually recovers (mostly from buds lower down on the stem and closer to ground level), the same situation can arise with poor bloom following that event. Last winter (2022-3), for example, we had a cold snap following a mild spell in late December, and plant damage still manifested from that even well into spring 2023.

Were the shrubs pruned at all between last fall and now? If so, flower buds were likely accidentally removed. Accounts vary for the 'Shooting Star' variety in particular, but overall it appears to be less cold-hardy than most others, grown mainly for "pot plant" use (that is, grown in greenhouses for potted display indoors while in bloom). Other hydrangea varieties, like those sometimes marketed as a flowering potted plant around Easter time, can be similarly cold-sensitive since they are not bred to be long-term landscape shrubs. (At least, not in our climate.) If your plants have survived prior winters with no problems, either this season had too much of a temperature fluctuation at some point, or the plants may have had pruning or deer browsing damage as a reason for their poor flower bud production. Drought stress can also impact flowering on any number of plants, and much of last year, most of Maryland experienced prolonged drought unless landscape plants were periodically watered. Plants stressed by drought can either forego forming flower buds or may form them only to have them die before opening.

Regardless of the reason behind poor bloom, adding fertilizer or compost won't necessarily improve flowering because a lack of nutrients probably isn't the reason for reduced flowering. A soil test is the best way to determine if any nutrient deficiencies actually exist in that location, as well as if the soil's acidity level (pH) is outside of the range preferred by these shrubs. (For example, soil that isn't acidic enough can affect how easily the roots can access nutrients in the soil. If pH is too far outside the ideal range, adding more nutrients by way of fertilizer won't correct the problem until the acidity level is changed.) If the hydrangea's foliage looked normal last year and not yellowed, then insufficient nutrients is probably not the problem. Compost is always a nice soil additive to help retain nutrients, improve drainage, and benefit root health, but by itself it also probably won't improve much if the rest of the plant grew normally. If you do add compost, only apply about an inch of topdressing (underneath any mulch that might be present) so soil life can gently and gradually work it into the root zone below.

Miri

Thanks, this is great information, I was told the same thing regarding the effect of last winters freeze on the hydrangeas, but I think the soil test would give me good information on what if anything I need for my soil. Thanks again , Steve

You're welcome.

I’m not sure if I  can ask another question regarding my Magnolia tree in Maryland otherwise I’ll re submit on the website. What is the best time to prune back my Magnolia tree which has just recently bloomed, thanks , Steve

Magnolias bloom on old wood so you should prune after it is finished blooming. You can do so an time after until about July when it is setting flower buds for the next spring. If you prune after that it would just be removing next springs blooms. 

It shouldn't need much pruning other than to remove dead or broken branches, or to remove crossing branches to maintain healthy branch structure. You can remove any suckers or new growth at the bottom any time. 

If you need more guidance for pruning, you can visit out tree pruning guide. Feel free to send us a photo of the Magnolia if you have pruning questions. 

Emily

Thanks again, Steve

I have 2 tulip plants with about 8 bulin the plant and want to know if I can seperate the bulbs and plant them separately or do I have to plant it as one plant , thanks Steve

Hi Steve, 

You can separate and plant them to spread them out. In the long run that will be better for them. They may take a few years to take off and fill in. Make sure you are planting about 6 inches deep. 

Emily

I’m glad you said I could seperate them because they fell apart when i attempted to plant the whole plant! Thanks again

One more question, I was reading about making some kind of water basin for the tulips with mulch , is that advisable?

Great info again , I might have to take a few gardening classes, thanks again 

I have two questions about my peonies and my boxwood , how do I send pictures of both in order to get some feedback on what’s happening with them ? , thanks steve

Hello Steve,

We prefer that questions unrelated to the original submission be sent in a new question submission, so it's easier for us to keep track of the conversation over time, especially if a discussion thread involves lots of photos to comb through. When you submit a question, there is a place on the submission form to attach up to three image files. The alternative is to paste images directly into the body of your question or reply.

It may be helpful in this case to submit one question each for the peony and boxwood to keep them separate (which will also let you more easily send enough photos for each), but you can do them together if needed. It helps to have each image file be at least 1MB in size so we can magnify it if needed. Over 8MB in size and the Ask Extension system will reject it as too large of a file.

Miri