Install a Tree Guard

Well, not all tree pit dirt is hard, though yours might be. You can check it by digging with a spade or stick. There is also tool called an “airator” (sp?) with two 4-5″ tubes you push into the soil that can help break it up more safely than with a spade. It costs about $20 at Lowes.

The link you put up is useful; it recommends loosening the top 1″ to 2″ of soil with a hand cultivator and then planting things with shallow (1″ to 2″) root systems, rather plants which need more space below ground like large bulbs. Specifically, it suggests small annuals like impatiens, which has a nice flower. It also suggests Periwinkle – I think this has a flower and would also work. Your best best might be small bulbs: the link suggests crocus, miniature daffodils, or glory-of-the-snow (Chionodoxa species).

Good luck, happy planting!

– Jen KG

I recently took a course at the Brooklyn Botanic Garden to become a Citizen Pruner (a person authorized to prune and care for trees on the streets of NYC). The head arborist at the Garden, who taught the course, very highly recommended against adding anything to tree pits that would raise the level of soil or mulch above the tree’s natural base. The base is where the trunk flares out but is still bark covered. If you put too much mulch or soil above the base, the base will rot and the bark there will be damaged. The exterior bark is the part of the bark that carries nutrition up and down – it is critical to the tree’s long term health. It is a great impulse you have – always wonderful to give extra care to the street trees! – but please be careful not to accidentally harm the tree while you’re beautifying it!

Rather than building a box that raises the soil level, just carefully hoe the soil at the base of the tree, add some fertilizer, and put your plants right there. Good luck!

– Jen KG