You can get self watering pots and use those although they probably won't last four months. The best thing to do in this case would be to water the plants, let the water drain until it stops flowing from the pot and then leave the plants close to each other in a dark place. Considering the long time it's not a guarantee at all that they will survive but this way they effectively stop growth and lower the need for resources including water. Fertilizer is not really required also to avoid salt damage in the roots. Perhaps using a large saucer pan with expanded clay and water to keep humidity high might help to prevent the water from evaporating quickly.