The hardest part irrigation form a barrel is getting enough pressure to push water along the soaker hose. Unless you elevate the barrel significantly it will not produce enough pressure to move water along the entire length of hose. The second problem is that water from a barrel may have small diameter pieces of debris or particulates that will clog your soaker hose significantly. A filter is usually needed with then reduces the pressure even more. You will be surprise how fast 50 gallons is used up during hot weather with mature plants so frequent refill becomes a chore. Also, to make a leak-proof connection to the tank is not easy as well. There are solutions to these problems. If your interested I can suggest them. Aloha

I can definitely elevate the barrel enough and I have a timer on it so it can only dispense water at the times I specify. I would fill the barrel at first with water then balance that out with rain water. This is mostly for days I cannot water the plants and for when I go away. I do have a filter and I'm definitely worried about leakage but as I mentioned I mostly want to use this as a back up and monitor it for a while to see how things go. So yes I'm definitely interested :)

UG,

Well, the most fail-safe method is with a submersible pump that produces pressure around 15-20 psi and can be on a timer for start and stop times. Therefore no holes in the tank. No elevating the tank. The wire and outlet hose go over the rim and not through the tank wall into a filter and works with a soaker type hose.

Now if you want to gravity flow from the tank, you have to elevate the tank 20 feet to obtain 10 psi when tank is full. As the tank empties to the bottom, the pressure reduces to 8 psi. Anything lower and the soaker hose plus filter will not operate consistently with higher risk of clogging (lower flow rate at some orifices and none at others). You can get flow at a lower pressure but not with a soaker hose. The fittings that would go through the side or bottom of the tank need to be a compression type fitting. Screw type that squeezes gaskets on either side of the tank wall. Check out Nylon fittings by WATTS. I also used a pvc union fittings to go through a tank wall with rubber gaskets. JMHO Aloha

I'm currently using rain barrels as my main source of watering. I have 4 50gal barrels, a on deman 6gph water pump connected to a 12v deep cycle connected to 15watt solar panel to charge it. From the barrels it connected to a filter Then water pump then 2 way splitter, one is on a timer to my garden and containers iriggation. Other on a hoe for Normal use. It's work out good, only little problem it's seems like I'm always running out of water, so I might add a few more barrels in the future, but its has been raining in fl everyday , so it works out fine if my barrels getting low, it will refills it for half a week the. So on. One thing about rain barrels, I need to filter atleast twice, one is where the rain gutter water comes in then another is when before the water enter the water pump. Because u don't want debrise to clog up all your hoes. Make sure you spray paint your barrel if it's clear white to prevent mold build up which the result of clogging up your pipes and having to take it apart/wasting water to clean it inside.

If you are going to use rain barrels, Lee Valley Tools sells a fitting that you can screw to a barrel that gives you a tap.

Put a water filter in place too. You need about 3 feet of elevation to provide reasonable pressure to operate the hose. That will give you 2-3 psi, about 1/20 that of a tap. So what you could water with a tap in an hour will take you a day with this setup.

Since the barrel has to be elevated, it's hard to hide. Sand the barrel lightly and latex paint will stick reasonably well to it. Make it art.