This companion planting is by mere of coincident. I didn't plan what to plant in the raised bed earlier, i just dumped everything in to save space. And surprisingly they grew well together, except that the carrots never fruit, but the foliage was so good. Hmm. Maybe too much nitrogen like what Diana said?
I'm not very sure why these plants like each other and how these plants help each other but you can refer here for companion planting list- See that? Carrots, daikons and lettuces are in one group- how good if i have luck in lottery too haha.
The raised bed
Carrots and daikons
Lettuces, daikons and marigolds at the other side of the bed
I have read many pages on the internet saying that marigolds are famous for companion planting as they exude chemicals from their roots or aerial parts that suppress or repel pests and protect neighbouring plants. I follow to grow them everywhere in the garden for the sayings and to add a touch of colour in the vegetable garden. But so far i'm not aware of any real research were this practice has been proven to be effective?
Do you have anything good or bad to say about your personal experience with marigolds? Are they really a good companion plant? Come let's share with us.