I have been told several ways to water my bonsai and pre bonsai material.
One method is using a water can and letting the waterrun out of the bottom. Stopping for a minute and then rewatering until it runs out the bottom.
Second method is taking a bucket and putting the plant/pot in the bucket and filling it with water over the pot and up the trunk. Letting it sit in the water for 10min.
Third one is to water with a water can and let the water run out once..
Any points on this would be great.
Ideally, you should get sufficient rainfall each day to water your bonsai thoroughly.
Since you probably won't get that ... here's my take.
Watering may be the most complex (while important) part of the whole endeavor. Unless you're using collected rainwater you're starting off at a great disadvantage whenever you open the tap. All municipal water is treated with chlorine in one form or another. Though chlorine is a micro-nutrient for plants, you'll get it in excess when watering with chlorine-treated water. This can cause harm to your bonsai.
Soil pH typically goes too high if you water with tap water for too long. This does not occur so much in your yard, as the typical clay content of soil acts to buffer pH. You don't have this benefit with most bonsai soils, as there is little to no buffering capacity. So ... in time your pH drifts above 7.0, and ultimately your soil will become water-resistant to a degree. This is another way to say it doesn't "wet" as well when the pH is alkaline. This not only dries out roots but locks up nutrients vital to your bonsai's health.
Alkaline pH can be treated effectively by using a product such as Miracid or 1 tablespoon of white vinegar to each gallon of tap water. This lowers the pH from around 7.5 to around 6.5, which is just what you need.
What's the best way to water with tap water? I've used a hand wand, hand sprayer, watering can, misting system with timer, spray heads and timer, and even have immersed a handful of trees in 20+ years. When watering by hand I water at least twice during the session unless I'm short of time. When doing this I watch closely for signs of poor wetting, such as water lingering on the soil surface when it shouldn't be. If I'm getting drainage in under one second I know things are all right.
If you have only a few bonsai then you could do immersion, though I see no special need for it and it is a pain. It won't solve an alkalinity problem though you will get water to the roots this way. Because I grow commercially the only viable solutions for me are to use spray heads and a timer during summer heat, and to hand water with a hand wand at other times (twice per day spring through fall, once per day in winter unless the soil is frozen). It's really important not to rely totally on your timer and spray system if you use one. Sometimes a tree will grow enough while you're not looking to shield its neighbor from the spray. So be sure to at least inspect to be sure everyone got their daily bath.
For what it's worth.
Zach
