Do you need to take a guided tour of Keukenhoff Gardens to appreciate it and see the best displays?

You can see every inch in 3-4 hours if you want to. You can say you saw it, with 2 hours. Historically, it is very crowded and a tour would not alleviate that. We enjoyed it. There may be little live concerts or special events.

We went in the last week of April in 2019 and arrived on Easter Monday morning about half an hour before opening time. It felt like there were a fair number of people waiting with us, but once they opened the gates and people spread out it felt like we had it almost to ourselves. If memory serves, we spent about 3 - 3.5 hours there just wandering, no tour, and it was pretty magical exploring it in the lovely morning light with minimal crowding and the ability to roam as we wanted. By mid/late morning it was much more crowded.

All that to say, I don’t think you need a tour - I recommend going super early to enjoy exploring without too many people around! A few hours will be plenty. Two would have been enough but we love flowers and spent a bit more time as a result.

No, you do not need a tour. You can book entry tickets along with a bus ride to get there. My advice is to go early in the am before the big crowds. If you are there early you will be able to take photos without a lot of people in them. After you walk around the gardens take a bike ride out to the tulip fields, it is great fun! The bike rentals are right there in the parking lot.

We did not take a tour and had a wonderful experience exploring Keukenhof during the height of tulip season.

You do not need a tour to wander and enjoy the outdoor and indoor displays. We were there in April 2018 with a family from Leiden so we walked pretty slowly and stayed 3+ hours. We arrived late morning and it was crowded but we were comfortable strolling around behind a pram. We noticed by early afternoon the crowds really thinned out and by the time the baby’s dad joined us we almost closed the place down by ourselves. So go early or late, on your own with reserved tickets, for the least crowded conditions would be my choice.

I see no need for a tour. We arrived as soon as it opened in order to mitigate the crowds as much as possible.

I plan to visit Keukenhof in April too. I though about renting a bike in Haarlem to get there and tour around the fields in the area by myself after the park. Or is it better to take the bus there (maybe with the combiticket - even if I think a normal entrance ticket + bus ticket could be less expensive) and then renting a bike at the park?
Has anyone ever biked from Haarlem to Keukenhof? If so, how's the road? Too many cars?
Thanks!

I've done it from Haarlem. It is a bit further than I had expected having driven or taken the train previously.

Use the dedicated bike paths. Easy. Scenic. Lovely, especially adding in pancakes in the pancakery in the bos about half way.

I can't imagine using a guide for the Keukenhof. Get and use the map so you know where you are and wander as the spirit takes you. See what's on in the Pavilions so you know which to head for when the rain threatens, know where the food is (near the toilets or vice verse) and go left or right as you are attracted.

After several visits of 2 or 3 hours each I've still never seen it all. That's fine. Any area will be beautiful. I promise.

You certainly do NOT need a guided tour. You’ll be given a map and all kinds of information. Plus as you walk through the trails of this architectural wonder of flowers, information is available practically at each bed.

Arrive when the gates open when the mobs will not have arrived yet. It can be like an amusement park.