Foxglove flowers, toddler and landlord trouble?

i would like to know what the legal status is concerning the removal of harmful/poisonous plants/flowers from the garden of a rented house. i have a young toddler who is almost 3 years old and two older children aged 10 and 12 but i am not concerned about them as they know and understand not to eat or chew on flowers. we also have two dogs. recently some foxglove flowers have appeared in our front garden (well, actually quite a lot of them) and i know that the entire plant is toxic, and children who have only drank some water from a vase that contained foxglove flowers have died from it. i am always outside with the toddler but as they are all over the place i am really worried that if i turn my back or look away for a few seconds he might decide to taste the colourful flower. i have asked my landlord if i could remove the plants for that reason but he says that i am not to touch them, thereby litterally confining me and my toddler indoors. i agree that they are beautiful and if they weren't toxic to all animal species including humans, i would love to keep them, but i am petrified for my son's safety (and my dogs too). is it legal for my landlord to keep plants that are toxic? i have printed off a sheet with the info on foxglove for him and i will show it to him in the hope that this wil change his mind because i don't think he believed me that the plants are toxic. fencing the plants off isn't a viable option as the garden is not exactly big and there are pockets of them in several places as well as all along the front and side wall. please tell me what you think.