activation form only appears when a plant is added

imports/ui/ActivatePlant.jsx

@@ -54,6 +54,8 @@ class ActivatePlant extends React.Component{
     render (){
         return (
             <>
+                {
+                    this.props.plants.length !== 0 ?
                     <Form onSubmit={this.handleActivation}>
                         <Form.Group>
                             <Form.Label>Active plant:</Form.Label>
@@ -72,6 +74,8 @@ class ActivatePlant extends React.Component{
                         </Form.Group>
                             <Button type={"submit"} disabled={this.state.isActivationButtonDisabled}>Activate</Button>
                     </Form>
+                    :null
+                }           
             </>
         );
     }