To get the best our of your tree fern it is important to understand how to feed it. A newly planted tree fern should not require feeding in its first growing season as plenty of nutrients will be available to it in the surrounding soil. Once established the plant will need food as the frequent watering of the plants will soon leach the nutrients from the soil leaving it hungry! In the wild the species grows in wetland forests where the ecosystem can quickly break down compostable matter and return it to the soil, this probably isn’t the case in your garden to the same extent!
Trees ferns can use a surprisingly large amount of nutrition, and are able to produce a second flush of fronds. There is no magic formula to feeding tree ferns. Some poeple just use a normal soluble plant feed a couple of times a week. I tend to sprinkle fish blood and bone around the base of the trunk twice a year and cover this with a fresh layer of my potting mix. Other feeding methods include using chicken pellets either in the crown or around the base. As with all plants that you are looking to encourage foilage growth a fertilizer with a good amount of nitrogen is best.
You can find specialist tree fern foods on the market, these can be usefull as they have the nutrients in the correct proportions.
If you intend heavily feeding your tree ferns then it will be important to also water them regularly – at least twice a day morning and evening – so that they do not suffer with root burn.
Once the growing season moves into the autumn period it’s best to end feeding to allow the existing fronds to harden up for the winter. As soon as the first frond opens in the spring feeding can once again commence at the half dose concentration.