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hiddenspring_gw

Can I prune hydrangeas and loropetalum now??

hiddenspring
9 years ago

So we have some hydrangeas (blue and purple flowers - two types, and looking at some pictures online they are mopheads and lacecaps). I am not sure which cultivar as it was planted by the previous owner. Last summer I did not prune them and now they are overgrown in the front flower bed. Same for the loropetalums (we have the ruby red).

My question is would it be ok if I pruned these now (before spring) or would it drastically reduce the blooms this spring/ summer? I heard mopheads and lacecaps set blooms on stems from the previous season for the current season. Does this mean I should thin the bush out (i.e. cut 50% of the stems down to the base) so that I will still have some blooms or should I prune all stems to half the height?

Same question goes for the loropetalum. Thanks for helping me out with this!

Comments (10)

  • luis_pr
    9 years ago

    Hydrangea-wise, it depends on wether you care about the blooms or not. Hydrangeas that bloom purple and blue are Hydrangea macrophyllas; they come in two "flavors" that are called mopheads and lacecaps.

    H. macrophylla produces invisible flower buds in July-August and the flowers open on the following Spring so, you should have flower buds (invisible now) waiting to open in Spring 2015. These flower buds are located at the end of the stems. As a result, pruning is not recommended now if you wish to enjoy blooms. It is best to prune them in June although anytime after they bloom but before July is ok too as this lets you enjoy bloomage for some time.

    If you do not care about the blooms in Spring 2015, you can prune now. If this macrophylla is not a "rebloomer", you may not get blooms until Spring 2016 though. If it is a rebloomer (like the Endless Summer or Forever & Ever Series for example), it may produce blooms much later than usual (mid to late summer).

    Loropetalum is similar to hydrangeas in that it generates blooms in late Summer-ish so I would also wait after it has bloomed in late Winter 2015 / Spring 2015 before pruning it.

    Luis

  • hiddenspring
    Original Author
    9 years ago

    Thanks Luis. So we do care about the blooms in Spring 2015. Which means I won't really prune now based on what you have said. I do want to thin the bush out - which means 1) remove branches that are growing outside the flower bed and 2) remove any dead wood. Should I just prune these or cut these as close as possible to the base? Also is there a trick to identify dead wood? There are still some branches that have the dried out flower from late fall 2014. Would these really flower again in Spring 2015 or is it safe to prune these? In 2014, I did see some branches already existed while there was new growth of more branches from the base of the plant. I don't remember which ones bore flowers....

    Also in June 2015 when I prune, I can just cut the branches to half their original height correct? Or whatever I wish? Idea being the plant will sprout new growth in July/August and set buds for Spring 2016?

    Vijay

  • luis_pr
    9 years ago

    Dead wood can be pruned close to the base if you do not see any leaf out by mid-May. That is an at worst scenario and usually applies to pants in their first year of being planted. Yours should definitely leaf out much earlier but it is ok to wait.

    The lazy approach to identify dead wood is to wait. You can also use your nails to scratch the stems and see if you notice green or not.

    You can leave blooms from 2014 for winter interest or you can cut the string that attaches the bloom to the stem. That is called deadheading and you can read more about it in Method 1 of the link below, under Removing Old Blooms. These could produce blooms so better leave them alone until June.

    And if you have any dead stems during the growing season, feel free to cut them at any time.

    When time comes to prune in June 2015, you can give them a buzz and cut the stems by a quarter or in half. The plant will then trigger some new growth and invisibe flower buds at the 'new' ends of the stems. From those flower buds, you will get blooms in Spring 2016.

    Other people cut 1/3 of the longest stems down to the ground on Year 1, the second longest get cut in Year 2 and the rest on Year 3. It is called rejuvenating and is done every 5-10 years when you notice bloomage problems in terms of size and number.

    Luis

    PS - I would do a soil test, even if you end up using those cheap soil test kits, to see how the nitrogen/phosphorus/potassium levels are.

    This post was edited by luis_pr on Mon, Jan 19, 15 at 20:02

  • gardengal48 (PNW Z8/9)
    9 years ago

    Luis gives great advice but I'd like to caution you about some of the timing. "Pruning" Hydrangea macrophylla is a tricky question at best and the timing of any contemplated pruning will depend heavily on where you are located and the exact type of mac you have. Generally, the recommendation is to prune any mac as lightly as possible. Deadheading can be done at any time as can the removal of deadwood but actual 'pruning' - cutting back live stems - should be approached with caution (with the exception of rejuvenation pruning).

    For example, H, macrophylla does not bloom in spring in most parts of the country, so a June pruning is not encouraged. In my area, this shrub has not even bloomed by that time of year! In most areas, this is a summer blooming shrub (late June into July and with flowers produced well into late summer or early fall). Waiting until after the bloom period would put you well into fall, which is not an ideal time to prune anything! I usually instruct clients to get by with the least amount of pruning they can manage to maximize flowering but the rejuvenation method is great for reducing size/shape while maintaining some/most flowers. Or if a really overgrown or oversized plant, a one-time hard pruning will get you working again with a better sized plant but you will typically miss an entire. bloom season

  • hiddenspring
    Original Author
    9 years ago

    Thanks Luis and Gardengal for the tips.

    So at least one thing is clear in my mind. .. I won't prune them right now. I do want to prune them the next opportunity I get because they do look overgrown already. Attached is a picture.

    I can't remember when they started blooming last season but I definitely remember blooms in June July and a spurt of some late blooms I believe in September? So if I understand this correctly if I prune in July or before i will lose the blooms that are supposed to come in July - September and if I prune in August or later I will lose the blooms for next season.

    Essentially there is no good time to bloom, which brings me to rejuvenation. Would you recommend that as a better option overall to pruning everything in this situation? I like cutting 1/3rd of the branches because other than the overall height the other issue is the density of the branches - it will give more breathing space to existing branches. If I do that - should I do it in June/ July next year or now itself? It seems easier to do now just because it's much more accessible.

    Thanks again
    Vijay

  • luis_pr
    9 years ago

    Wow! For that type of pruning -where you do not care about the blooms- you can cut 1/3 of the stems now (or whenever). But now is better because you can see what you are doing more clearly. Lord knows I would not be able to untangle those shrubs even if I had to! Hee hee hee!

  • hiddenspring
    Original Author
    9 years ago

    Ha ha ha - I know right - it looks so messed up! I think if i remove the tallest branches right from above the soil level, it will look thinner and hopefully better and I will still get half the blooms but it will look more organized... well at least that's my hope :-) We will see.

  • luis_pr
    9 years ago

    Have fun pruning them!

  • paintcan
    9 years ago

    What is pruning direction for hard frozen hydrangeas?

  • luis_pr
    9 years ago
    last modified: 9 years ago

    Generally speaking, you do not need to prune hydrangeas unless there are safety issues or branches that cross or it is planted in a spot where it overflows into other stuff or people. Varieties like H. macrophylla (aka mopheads or lacecaps), H. quercifolia (aka oakleaf hydrangea), H. aspera, H. serrata and Climbing Hydrangea, they all develop invisible flower buds between July-August and these open in Spring 2015; they should not be pruned now unless you are "ok" with cutting off the flower buds for Spring 2015. You could prune after they have bloomed but before July-August. Some of these varieties will rebloom several times throughout the growing season so, if your hydrangea reblooms, you can prune it at almost any time and still get some bloomage. Varieties like H. paniculatas and H. arborescens develop flower buds in the Spring so they can be pruned now if you need to prune them. Paniculatas and arborescens can be pruned at almost any time except close to the time when they bloom in your location.

    You can deadhead the spent and dried out flowers at any times by cutting the little string that connect the bloom to the stem. Note: do not cut the stem itself. See the link below for information on pruning and details of the difference between deadheading and pruning:

    http://hydrangeashydrangeas.com/pruning.html

    Hope that helps, Luis