How to keep those cut flowers looking their best

To keep cut flowers fresh, place them in room-temperature water as soon as possible. With a sharp knife or pruners, make an angled cut at least 1 inch from the end of each stem. Ideally, make this cut while the stem is under water to avoid getting bubbles of air in the stem. Cutting on an angle increases the surface area for water intake. Remove all foliage that will be below water level.

Add floral preservative to the water in the vase. Most preservatives contain an acid to neutralize alkaline tap water and an ingredient to discourage bacteria.

When you bring cut flowers, be sure to protect them from freezing temperatures outside.

Cut flowers will last longest in a cool, humid environment and should be kept out of bright light and away from heating vents. Do not place cut flowers close to a bowl of fruit or vegetables, since the ethylene gas emitted by ripening fruit can damage the flowers. So can cigarette smoke.

If healthy cut roses suddenly develop drooping heads, it may be due to air bubbles trapped in their stems.

To revive the bloom, float the entire stem, flower and all, horizontally in a sink full of warm water. This may allow the air bubbles to escape and the vessels of the stem to fill with water. With the end of the stem below water, trim another inch from it, cutting on an angle. While the stem and flower continue to float, try to gently straighten the drooping flower head. Keep the cut end of the stem under water for at least half an hour. When the flower head firms up to a straightened position, place the rose back into the water-filled vase.

Continue putting organic material from the kitchen into your compost bin during the winter. If you are using a free-standing plastic composter, the material will be secured against dogs and other animals.

Compost can be used to amend soil or as a mulch layer on garden beds and around trees. It is the end process of composting, a process in which organic matter, chiefly from plants, is collected, mixed and allowed to decompose. Composting improves soil and reduces the amount of garden debris that ends up in landfills and improves your garden's soil.

In nature, leaves and dried stalks and stems create a mulch layer that eventually decomposes. Like human-made compost, this natural recycling process returns nutrients to the soil and improves soil structure, and it is one reason why native plants growing in natural ecosystems usually do not need more fertilizer than nature provides.

• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.