Update: Okay, here is what I found:

Manzanita (Arctostaphylosis) a native plant of CA, and blooms in winter or early spring. You can check with the nurseries below, but I doubt if you will find a Manzanita cultivar that blooms in August, and may not be small enough for your purposes. I found a gardenia topiary tree that is support to bloom all through summer. See below. Also, daisy topiary would be a good possibility. I hope this is helpful.

http://www.laspilitas.com/nature-of-california/plants/349--arctostaphylos-baby-bear-manzanita-bush

https://www.anniesannuals.com/plants/view/?id=3639

http://www.yerbabuenanursery.com/viewplant.php?pid=149

http://www.joycreek.com/Arctostaphylos-densiflora-Sentinel-410-014.htm

http://www.nativerevival.com/arctostaphylos-sentinel/

http://www.pacifichorticulture.org/articles/arctostaphylos-for-pacific-northwest-gardens/

http://www.laspilitas.com/groups/manzanita_arctostaphylos/Manzanita.html

Notes: August Gardenia (no experience with this plant, so make sure it can bloom in late summer; also ask other nurseries below if they had this plant before: https://plantinfo.umn.edu/search/plants?search=Gardenia&type=All

Check with the retailers below for a late white flowering topiary tree below…Maybe a Chrysanthemum, Gardenia or Hydrangea (not many shrubs flowering in August usually).

Beautiful and high end nursery in CT www.whiteflowerfarm.com/

NYC Flower District https://www.associatedcutflower.com/register.asp

Another great supplier of hundreds of plants in CT. https://www.logees.com/catalogsearch/result/?q=lemon+tree+topiary

Happy hunting!

Previous answer: 

Hello, and thank you for your question. Manzanita branches are used for weddings a lot, a good choice to show off many decorative items, since it has a multi-branched shape. Not sure what other branches would do as well. Do you mean something like this, with table cards around the decorative tree (see below).  You can go to the craft store, or in NYC the flower district which is filled with dried branches, decorations and more.  The flower district is on 28th street, between 6th and 7th avenues.

Branch decor: https://www.google.com/#q=manzanita+tree+branches&tbm=shop&spd=7893521969905611581

More ideas: https://www.google.com/search?q=Tree+holding+glass+globes+wedding+decorations&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiPnLbHwanUAhVPxCYKHfOnCesQsAQIOw&biw=1120&bih=573#tbm=isch&q=wedding+tree+table+decorations&imgrc=Cy_39GFzIw2_pM:

links: (we can not recommend retailers) but here's a good one with supplies and many ideas. http://www.save-on-crafts.com/weddingtrees1.html

https://www.jamaligarden.com/ (nyc flower district)

Hope this helps.