Hello, Thanks for getting in touch. Hydrangeas and Spirea have different water requirements. The hydrangeas really like water (hydra=water!). Spirea, on the other hand needs much less water once it is established. Unless we are in a drought, you may not need to water it at all. A gallon, twice a week should be enough to get the spirea going.

For the hydrangea, the best way to know if i needs water is to feel the soil. It is going to be more picky about drying out. Use a screwdriver, it should go into the ground easily and may even have a little bit of soil stuck to it when you pull it out. The soil should be wet, but not soggy. Water once or twice a week with about an inch of water. Depending on your flow, that could be 20-30 minutes. CSU extension has a fact sheet on deciduous shrubs. If you do a search for CSU fact sheet 7.415, it should be at the top of your search results. Good luck with your shrubs!

Oops. photo 2.

Hi Les, Figuring out how much water requires a bit of investigation. One inch of rain water equals 62 gallons. Below is a link to fact sheet re: watering. Your question requires more information about the soil. Drainage. Sun, shade, etc. The fact sheet gives instructions for measuring water hose vs rain water. https://extension.umn.edu/water-wisely-start-your-own-backyard/watering-vegetable-garden#.XwXqbbH6vO0.mailto Regarding the ground cover, I am not able to identify it by leaf shape. Is the cover perennial, evergreen? When it blooms please send Ask An Expert more photos for identification. Thank you for your questions. We are here to help with all your garden and landscape questions.

Thanks. Much appreciated. A couple of additional questions:

1. One of the spireas I planted in the fall is browning, the others are green. I am attaching a photo. Perhaps too much water or a pest. Your thoughts?

2. Can you tell me the name of the ground cover in this photo?

Hello, I'm looking at the photo you sent and I can't get a good look at it, but it does not appear to be a spirea to me and looks possible to be a cinquifoil (potentilla). If that's the case too much water could be an issue. Keep it evenly watered, but not too much.

I see also there is a weed mat near the plant. These can sometimes restrict oxygen to the root zone. Make sure there are adequate holes for oxygen to enter the soil profile.

The groundcover plant you sent looks to be plumbago. It gets these beautiful blue flowers through the summer and the foliage turns a lovely red in the fall. It does well in shade & is late to push through the soil in the spring.

I hope this helps & good luck,

Thank you. I transplanted some plumbago from the plant whose photo I sent, last fall. Wondering how much water you recommend me giving it at this time. The transplanted plumbago have a few leaves at this point and no flowers. Maybe 8 transplants in a new location, all quite small with, as I mentioned maybe a 3, 4 0r 5 leaves.

It is a late bloomer and I am just starting to see flowers on the ones I have in my yard. New plants may take a year before you see the bloom however.  Keep it evenly moist, but not water logged. It is a plant that prefers cooler, shady environs, but does OK in sun as well.