The Time Garden is a sequel to Knight's Castle, and a fun one at that. It follows the same kids (children of a couple of the original children), and includes a mysterious creature called a Natterjack.
The Story: The children are sent to spend the summer at the house of strange old Mrs. Whiton, and in her garden, they meet the Natterjack, who is kind of like a frog. He introduces them to the mysteries of the many different kinds of thyme growing in the garden. Each different type of thyme evokes a different kind of magic, from wild thyme to common thyme, and along the way, they travel in time and meet their parents (in a cross-over from Half Magic. Or maybe Magic by the Lake. I don't remember which one). It's very cool.
The Good: Did I mention it's just really cool? The adventures are lots of fun, and fast paced. I love how it overlaps with the previous stories, and it is just plain good reading. Plus, the Natterjack seems to speak with a cockney accent, and I love any excuse to practice fun accents. The kids don't care if I'm bad.
The Bad(ish): There are a couple tense moments along the way, but even my hyper-sensitive child didn't have too much trouble with them, so it's not too bad.
The Verdict: Love the time traveling, and the puns with the different types of thyme sending them on different adventures in time. A very clever person could make some thyme-infused meals for the kids to tie in with the book. I didn't get that far (this time) but I do make a killer Lemon Chicken with Thyme. Can't wait to reread this one.