I'll start off this month's column with a fairly negative statement: "Most hobbyist first attempt at growing live plants will result in failure." Fortunately this doesn't have to be the case. There are many steps one can take to maximize the probability of success. This month I'll share those with you.
Picking the right plant species is the first step. Since algae is the most common cause of failure in planted aquariums, your initial plant selections should only be made up of hardy, fast growing, robust species which can out-compete algae for nutrients. My recommendation for anyone starting a planted tank would include species such as:
Most Amazon Swordplant species can also be included in this list if you have a tank larger than 50 gallons. Buy as many plants as will fit in your tank/budget, as this will help the plants establish quicker by eliminating nutrients which would normally be used by algae. Once the tank has stabilized, and algae is no longer a threat, the robust species can then be slowly replaced by more exotic types.
The second step to success is choosing the right substrate for the plants. There are many choices when selecting a substrate. It can be as simple as plain aquarium gravel, or as esoteric as laterite. My rule of thumb is: "always mimic nature". Almost all plant species will thrive when planted in soil. I've found african violet soil to be quite excellent - it contains a lot of nutrients and organic substances necessary for luscious plant growth. Unfortunately placing soil directly in an aquarium will result in a tank of mud soup, which is probably not acceptable if you want to see your fish!
A technique I've found to be quite successful is to use plastic margarine containers as pots. Cut the top of the container so that the bottom half is about 4-5cm high. Put about 1-2cm of soil in the container. Place and hold the plant upright, and add more soil to fill the container. Slowly wet the soil with some room-temperature water, then gently pull the plant up to very faintly expose the start of the root system. To prevent the soil from washing away place aquarium gravel in the container to completely cover the soil. Once you've decided where in the tank you want to place the plant, turn off the filter and any air pumps to minimize water turbulence. Slowly lower the potted plant into the water, and then 'landscape' the gravel around the pot to hide it. Turn on the filter and air pump.
For larger plants like Amazon Swordplants, I would recommend a very large container measuring about 15cm x 15cm x 10cm deep. South American Frogbit is a floating plant and therefore need not be potted. Water Sprite has two states, floating and planted - I would recommend leaving it floating for the first month in a newly planted tank. Finally most Vals need not be potted since they spread by runners and seem to grow well on gravel.
I hope you found this month's column helpful. Next month I'll discuss two related plant topics - algae control and fertilizer selection. Bye for now...