Going to Monet's garden at Giverny had been a "bucket list" item for me, and I was able to make the…read moretrip recently while visiting Paris! It was such a beautiful place and did not disappoint. The flowers in mid-April were beautiful to see, with huge peonies, lots of tulips, crocuses, wisteria on the Japanese bridge, and other spring blooms. This also seemed to be a good time to visit as it gets more packed during the summer.
Tip: Rather than doing a bus tour, it was fairly easy to simply take the SCNF train to Vernon. From Vernon, there are regular shuttle buses directly to Monet's garden for 5 Euros each way (10 Euros round trip), so it is very straightforward. The train from Paris to Vernon leaves from Gare St. Lazare.
Also, if you do go via train to Vernon to get to Giverny, there was an adorable cat cafe there for lunch: Cookie's Cat Cafe!