Good morning, tmneese. I hope everyone is doing well, as I happened to notice the time of these posts and gee, shouldnÃ¢â‚¬â„¢t we all be sleeping?
Hee hee hee. My excuse is a dog with a sick tummy. Woke me up when I heard this Ã¢â‚¬â€œerr- sound
(please, no details!) and had to let her go out and eat some grass, weeds or whatever it is they like to do when this happens.
But I digress. LetÃ¢â‚¬â„¢s talk about your other sick patients as I wait for mine to returnÃ¢â‚¬Â¦.
Pruning recommendations for hydrangeas are somewhat similar to the good recommendations already given by Kisal. You can prune stems that cross, those that are growing too much and Ã¢â‚¬â€œof course- those have dried out. Security, plant variety and aesthethics should dictate when and what to prune.
If there is hazard caused by all this hydrangea growth, prune as soon as possible and do not be concerned about missing blooms in Spring 2010. It is a must do.
Contrary to rhodies though, hydrangeas may bloom on old or new wood. This may let you prune now and still get flowers after all. Do you know what type of hydrangeas you have and the name of the variety? The type can be the well-known macrophyllas (mopheads and lacecaps) or oakleafs, paniculatas, arborescens, asperas, serratas, villosas, etc.
Macrophyllas are the ones that can bloom on either new or old wood but that depends on the variety. The Endless Summer Series, for example, is a macrophylla variety that can be hard pruned now and will still produce blooms next year. Other macrophylla varieties, like Nikko Blue, start developing flower buds now (they are not visible) and pruning [i]now[/i] would result in no blooms next year. In the future, you can prune according to the type of hydrangea that you have.
Mopheads and oakleafs can be pruned after they bloom but before they develop flower buds so make a habit of pruning these in June. Every 5-7+ years, you may notice lackluster bloom production some times. You can rejuvenate the shrub by pruning 1/3 of the stems each year until you have pruned them all. Prune as close to the base or crown as you can. You can start with the 1/3 oldest and longest stems. All other forms of heavy pruning can be done when the macrophyllas are dormant, to reduce shock to the system.
Paniculatas and arborescens always bloom on new wood so they can be pruned at any time except when they are about to bloom. Arborescens start to bloom in the Spring and Paniculatas start later, in June-July.
Plant material resulting from all this pruning can be composted provided you do not have fungal problems with the plants. If you do, dispose of them in the trash (in plastic bags).
Regarding your rhodies, you may want to forget about doing any pruning if their health is so-so. Instead try to determine what is causing the problem and address that. If you have to prune and if you can wait then minimize shock to the plant by pruning in winter. To me, it sounds as if there may be a watering issue. Try to consistently keep the soil moist, not wet, at all times and provide 3-4" of acidic mulch so you do not have to water often. As a safety check, look for evidence of bark split or borers. These could also cause browning of sections of the plants. Plants like these that are in stress should not be fertilized.
Rhodies are best pruned after they finish blooming. Pinch at that time to make the plants denser.
With large-leaved rhodies, prune just above growth joints that are formed at the beginning of each growth season. Dormant growth buds are located below that spot.
For small leaved rhodies, prune anywhere on the stem because these shrubs have adventitious dormant growth buds all over the stems.
Have a good evening guys!