UNITED STATES—Where winters are cooler, the deteriorating stems of flowers that bloomed last year either got pruned away already or got knocked down by the weather, and are now rotting on the ground. Around here, where the weather is milder, and some flowers only recently finished blooming, used up flower stalks still stand in stasis. Most but not necessarily all should get pruned out and raked away.

Dahlias succumb to frost as soon as it arrives. If not already cut back, they fall to the ground like steamed spinach, and should get raked up and put into greenwaste. There is nothing to salvage. Sunflowers are related to dahlias, but do not collapse so easily. Even if they are not pretty, those that produce seed can be left for whatever birds like to eat them, and then recycled when empty.

Of course, not all of the seed must be left to the birds. Some or all can be saved for next year. The flowers only need to be allowed to dry so that the seed matures. If the birds start to eat them first, old flowers can be cut and stored in open bags or boxes in a shed or garage, out of reach of birds. Stems should be cut longer if they are still green. Seeds should fall from the flowers as they dry.

Seed can also be collected from lily-of-the-Nile and African iris, although these perennials are so easy to propagate by division that growing them from seed might be more trouble than it is worth. Their seed capsules must be allowed to dry, just like sunflower seed. Belladonna lily makes a few weirdly succulent seed that are worth collecting. Some primitive cannas make weirdly hard seed.

It might be worth researching flowers that happen to be in the garden to determine if they produce viable seed worth collecting. It is also important to know what seed requires scarification or stratification. Seed that needs stratification must be exposed to cold temperatures to be convinced that it is time to germinate in spring. Canna seeds need to be scarified by filing through the hard shells before they germinate. Other seeds need other types of scarification or stratification.

Highlight: Austrian pine

Relative to other pines and evergreens that are commonly grown as living Christmas trees, the uncommon and even rare Austrian pine, Pinus nigra, would be a better option. If it gets planted too close to the home, as Christmas trees often do, it does not get big enough to cause major problems. Although much bigger in the wild, local trees may take decades to reach second story eaves.

The species is divided into two subspecie, which are each divided into three regional varieties, which is a fancy way of saying that individual trees may have distinct personalities. Generally, they resemble Japanese black pine, with similar irregular branch structure, but are more dense, and may get a few pendulous stems with age. The dark green needles are slightly shorter and stouter.

The Austrian pine was likely named as such when much of its natural range was still within the Austro-Hungarian Empire, which has since been subdivided into the countries east of the Adriatic Sea. Other larger parts of the range are in Turkey and Spain. Only a small colony lives within Austria, west of Vienna. Austrian pine likes full sun and warmth like it would get naturally back home.

Horticulturist Tony Tomeo can be contacted at tonytomeo.wordpress.com.