Why do hostas require shade?

Hostas do not require shade, they are “shade tolerant.” There are many degrees of shade, ranging from sites that never receive any direct sunlight, like the north side of a building or the dense, low covering of large trees in a heavily wooded site, to open, filtered and dappled light coming through the canopy of smaller leaved, more open trees. Also, direct sunlight in the afternoon, between noon and 4:00 p.m., is much more intense than morning or late afternoon sun.

The amount and type of shade will affect the selection, placement and performance of hostas. In general, avoid placing them where they would receive sun between noon and 4:00 p.m. Yellow or gold-leaved hostas need some sun to develop their brightest coloration. It is frequently stated that a yellow hosta will brighten up a dark spot. This is true, but they often don’t do well in such locations, as they find them too shady. The blue coloring of some hosta leaves, called pruinose or glaucous (characterized by a waxy, silvery coating), will last longer if the plants are grown in light shade. In general, green-leaved hostas can take a fair amount of sunlight, although the leaf coloring will be dulled considerably in too much direct sun.

For any hosta, too much sun, combined with lack of water, will scorch the leaves, especially in July and August. For variegated hostas, placement will depend on the most dominant leaf color, usually the center coloring. For instance the hosta ‘Gold Standard,’ with a dark green border, needs sunlight in mid-season to have its chartreuse center change to a handsome parchment gold. In a very shady site, it becomes just a yellowish-green. Given too much sun, the center turns first to a gold and then to a light, creamy white or even a near white.

If the shade is dense, your hostas will not be as vigorous; they may even decrease in size each year. Some trees have greedy surface roots that will compete with the hostas for water and nutrients. Hostas don’t like such competition, so if possible, plant your hostas far enough away from trees to avoid this problem. Experiment in placing your hostas. If one doesn’t do well in a certain location, move it to another, or replace it with a different variety!

This past winter wreaked havoc on my 45 rose bushes – mostly hybrid teas, some floribundas, and some Old English climbers. Except for the climbers, I had to prune the others severely. At that time, I did not put anything on the cuts as some suggest (like white glue). Is it too late to put something on them, even though that part of the bush is dead and brown? For the most part, the roses looked pretty good this summer, although I would have liked them to have thicker, stronger canes. What is the best fertilizer I can use now to help them through the upcoming winter? Is there still hope that these roses will do better next year?

It was a hard time for many plants that have enjoyed several mild Michigan winters. At this point there is no reason to put anything on the prune cuts. The plant has already healed over. Trim out excess dead wood to just above the green portion. Leaving it over winter could cause bacteria to hibernate. Continue to deadhead and use preventative sprays against pests and diseases. The best fertilizer I have found is fish emulsion. Generally Labor Day is the cut off for fertilizing, as it overstimulates the plant to produce new growth before cold temperatures start. It’s better to water and mulch well with compost prior to bedding them down for winter. Take extra precautions against a hard winter by using rose cones (which can be unsightly and tricky to use properly), or surrounding your hybrid teas and floribundas with wire cages filled with leaves. The latter prevents winter desiccation and sunburn, as well as preventing animals from gnawing the canes.

As far as your climbing roses go, when the temperatures drop below zero, take your climber canes off their supports and secure them to the ground with crossed stakes. You can cover them with mounded soil or wrap them in burlap and leaves for protection. With a little extra care in winter preparation, your roses should be stunning once again.