Drip feeders are great for a variety of different vegetables, perennials and annuals. Many plants prefer the moisture at their roots instead of from overhead sprinklers which can encourage some leaf problems.
There are many retail products available, but this Soda Bottle Drip Feeder makes use or recycled materials and works really well.
Watering from the root area instead of overhead encourages a plant to develop a healthy root system and prevents fungus and other problems that overhead watering encourages.
You can, of course, use a retail drip feeder hose for the task, but this handy DIY tip will help your plants and make watering an easy chore.
Just take a large 2 liter soda bottles (BPA free is best for this use on vegetables, but normal soda bottles are fine for flowers and shrubs), and use barbecue skewers to poke holes in them. (We suggest using less holes than this image shows so that it would be a very slow release, but it depends on how dry your soil gets.)
Insert the soda bottle into the space next to the plant when it is young and leave the top off. Leave the top exposed. When it gets empty, just top it up from the hose.