How do I fertilize my giant sequoia bonsai?

It is important to keep the soil fertile for the giant sequoia. The largest tree on earth is also the heaviest feeder. It is best to use a type of fertilizer that can be accurately measured for application. Soluble fertilizers are the most idiot proof. Simply follow the instructions that the manufacturer provides. On the giant sequoia bonsai we use Giant Sequoia Bonsai Plant Food at the rate of 1 tablespoon per gallon. This plant food is available at http://www.giant-sequoia.com/sites/giantsequoia/cart/plant-food. During the growing season we fertilize the bonsais every two weeks. The more root bound bonsais require a lot of water when the temperatures are warm. Those may require watering up to four times a day. All that watering will leach the soluble fertilizer from the soil rapidly. Weekly fertilizing may be in order for those that require a lot of water in the summer.

How do I keep my giant sequoia bonsai over winter?

Young sequoias are not very sappy and are subject to freeze-drying. Freeze-drying usually only discolors and does not harm the trees but it can damage or kill the young trees if they go into the winter already dry. Keep them watered up until the ground freezes. Then if possible bury the trees in snow. In their natural environment the young ones are buried in snow all winter. You may want to construct a windbreak or find a box to place over them when the deep freeze comes if there is no snow. As the sequoias mature they become sappier and less vulnerable to freeze-drying. The cold is not a problem. The cold dry wind is. 

How do I shallow pot the seedling giant sequoias?

Remove the seedling from the container. Use a sharp knife to split the root ball beginning at about the halfway point and slicing downward. Spread the slices apart and place the tree green side up into the shallow pot. The root ball will be in the shape of an inverted T when placed in the pot. Do not remove any of the roots at this time. Cover the roots with good potting mix. Do not bare the roots of the giant sequoia. Keep the soil intact on at least 75% of the root ball. That will protect the tender little white roots that nourish the tree. If the white feeder roots are lost the tree will slowly die of dehydration.

How is root pruning performed on the giant sequoia?

We advise to avoid root pruning altogether unless you need to reduce the root ball size to fit into a smaller dish. Giant sequoias are able to self root prune to a large extent. Root pruning on a giant sequoia bonsai is performed successfully by slicing off a portion of the root ball with a sharp knife much like one would slice a block of cheese. Take only a conservative portion of about 20% or less. Never completely bare the roots of the giant sequoia. Do not be overly concerned with a root bound condition. Giant sequoias in the wild are naturally root bound for their entire existence.  Do your root pruning when the tree is dormant in the winter. Place the tree back in the shallow pot after root pruning and replace any missing portion of the root ball with good potting soil. Remove an equal or slightly larger portion of the tree’s branches at the same time. Avoid slicing roots solely from the bottom of the root ball. A portion of the bottom of the root ball can be successfully removed. The feeder roots tend to be most prevalent on the bottom of the root ball. Removing all of those can be harmful to the tree. If the root ball needs to be reduced in height remove soil and roots from the top of the root ball instead.  

How do I shallow pot the one gallon giant sequoias for bonsai?

Remove the tree from the container. Use a sharp knife to slice up to 2 inches from the bottom of the root ball. Place the tree in the shallow pot green side up. Fill the shallow pot with good potting mix. The top of the root ball should extend above the brim of the shallow pot by an inch or two. Use a garden hose with a pressure nozzle to carefully spray the top of the root ball removing some of the soil and exposing some of the upper roots. Do not trim the upper roots at this time. Allow the tree to root into the new mix before pruning the upper roots. Carefully prune some of the branches and foliage from the tree. A good rule is to remove an equal amount of foliage with each root pruning. That keeps the tree in a relative state of equilibrium. Do not bare the roots of the giant sequoia. Keep the soil intact on at least 75% of the root ball. That will protect the tender little white roots that nourish the tree. If the white feeder roots are lost the tree will slowly die of dehydration.

Can I keep a giant sequoia indoors for the winter?

A heated indoors is not a beneficial environment for long-term maintenance of giant sequoias. They will most likely survive the winter inside a house but will have lost their bearings somewhat concerning their dormancy period and climate adaptation.  It is helpful for them to spend some time outside in the cold of winter basically resting and getting used to their environment. Ideally the container kept sequoias will be watered well and then placed outside to be buried deep by winter snow. Once they are buried deep in snow there will be no maintenance needed until the snow melts in the spring. The trees will be insulated from cold drying winds and be unable to dehydrate under the snow. If you have freezing weather but no snow then the container kept sequoias will have to be taken into a garage or cellar occasionally to be thawed and watered. After a few days of above freezing temperatures and moist roots the trees can be set back out. They should not be set back out into sub zero temperatures. They will keep in the garage or cellar until the temperatures moderate some. The shock of rapidly changing temperatures should be avoided. The cold of winter does not harm the sequoias. Wintertime damage is done by wintertime dehydration from cold dry winds.