The Acton Arboretum is within minutes of my house (by car). The last couple of years it has been quite crowded, even mid-week, due to the pandemic and the number of children and adults "at home" and wanting to get out of the house. Things are a bit better now and I finally feel like getting over there with my camera.
It seems most serious flower photographers use a tripod. I do not. A tripod just takes the fun away for me. But I do carry with me a small fold-up stool that resides in the back of my van. This helps me get low and to hold the camera steady. When I put my elbows on my knees I become a human tripod.
Also helpful is that the Olympus camera I use gives me over 6 stops of image stabilization. In addition, I usually shoot at 1/250 second to reduce the liklihood of subject blur due to the small amount of flower movement I believe exists even on "calm" days. I typically shoot with an aperture of F4 and F8 and then choose the ones I like best when I am home and on the computer. F8 of course gives more depth of field. F4 gives better background blur. Less frequently I will use the in-camera photostacking feature with F4 ... this gives me the blurred background of F4 and the greater depth of field after stacking that I could otherwise only get with F8 or higher (i.e. narrower) F stops. I am happy with auto ISO; though if it gets too high (ISO 1600?) I will try dropping the shutter speed to 1/125.
My 2022 gallery of flowers photographed at Acton Arboretum is here: