sql - ORA-01843 Not a valid month -

i have seen of topics error can't seem understand people mean. codes:

create table vehicle ( v_id char (10) not null, v_model varchar2 (20) not null, v_manufacterer varchar2 (20) not null, plate_number char (10) not null, arive_date date  not null, pickup_date date not null ); 

this table , got dropped/created want insert these values in column keeps giving me error, looked @ other solutions bit different mine. might simple but, i'm new sql.

insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v100','bmw','430i','n-55530','01-02-2015','02-02-2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number. arive_date, pickup_date) values ('v102','lexus','ls300','m-33833','11/05/2015','12/05/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v101',' mercedes','e350','a-15553','23/04/2015','23/04/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v104','nissan','tiida','o-1885','31/09/2015','03/10/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v105','renault','duster','a-19994','15/04/2015','15/04/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v106','gmc','denali','o-60635','22/02/2015','23/02/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v107','ford','explorer','n-51951','11/08/2015','11/08/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v108','ford','mustang','g-33099','28/11/2015','29/11/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v109','jeep','wrangler','o-99199','22/09/2015','24/09/2015'); insert vehicle (v_id, v_model, v_manufacterer, plate_number, arive_date, pickup_date) values ('v110','dodge','charger','e-1370','14/04/2015','14/04/2015'); 

i tried changing format each possible option:

04/14/2015 or 2015/04/14 - 2015/14/04 or apr-14-2015. 

none of them seem work.

what want insert arrival date , pick date of following vehicles (belonging customers)

thanks.

always specific when have dates formatted text: conversion explicitly correct date/time format data.

to_date('14/04/2015', 'dd/mm/yyyy') 

do date inputs.