Annuals Change With The Seasons

50930thumbLike it or not, the warm season annuals that were so flashy all through spring and summer will eventually need to be replaced with cool season annuals to provide color through winter. It is always unpleasant to pull up the annuals of a previous season while they are still blooming, even if they are already getting scruffy and discolored. It is actually easier if they got roasted by recent warmth.

Some warm season annuals last longer than others. Many are actually perennials that can be overplanted with new cool season annuals as they get cut back or go dormant through their ‘off’ season. Some cur back perennials may not survive through winter; but those that do can regenerate next spring, just as the cool season annuals that obscured them all winter are finishing.

Wax begonias, for example, are warm season annuals that can continue to bloom until they get frosted. Where sheltered from frost, they only need to be cut back because partial defoliation exposes knobby bare stems. If they can be hidden by pansies or violas through their bare phase, they never need to be removed, and some will be happy to regenerate in spring.

Conversely, cyclamen, sweet William, chrysanthemum and some primroses are cool season annuals that have the potential to survive under the lush growth of warm season annuals next summer; but that is a topic for later. (Some people are allergic to primroses like poison oak.) Iceland poppy and ornamental cabbage and kale are not so perennial, but are quite colorful through winter.

Alyssum and nasturtium really are annuals that do not survive much more than one year. However, they can perform through summer where sheltered from heat, or through winter where sheltered from cold. In ideal situations, their self sown seedling replace deteriorating older plants, so that they can perform throughout the year. Nasturtium should be planted as seed, not from cell packs.

Calendula is a popular cool season annual early in the season, but may not last through the end of winter. Yet it is popular because it is so excellent through autumn. Chrysanthemums are even flashier, although they are often replaced as soon their first bloom phase finishes.

Start Cool Season Annuals Early

30925Twice a year, it becomes necessary to discuss the unpleasantries of pulling up the flowering annuals (as well as vegetable plants) of one season, to relinquish space for those of the next season. Just a few months ago, cool season annuals got replaced with warm season annuals. Now, those same warm season annuals will get replaced with cool season annuals for the next few months.

It is unpleasant because the outgoing annuals are probably still blooming when it is time for them to go. It might be easier to wait for cool season annuals to get roasted by hot weather, or for warm season annuals to get frosted. Unfortunately, by that time, the incoming annuals would be at a disadvantage. Hot or cold weather is also uncomfortable for plants that are not yet established.

Sure, warm season annuals like warmth, but only after they have sufficiently dispersed their roots to sustain their growth during warm weather. This is most efficiently accomplished while the weather is still mild earlier within their season. Cool season annuals likewise do not mind cool weather, but do not grow as well as they do during the warmer weather earlier within their season.

This is why it is better to plant pansy, viola, sweet William, Iceland poppy, stock, calendula and the various primroses earlier rather than later if possible. There is no exact science here. A forecast for warm weather certainly justifies delay. Cyclamen and ornamental cabbage and kale are a bit more sensitive to warmth, so could wait a bit longer. They grow well through cold weather anyway.

Chrysanthemum, alyssum and nasturtium are odd ones. Chrysanthemum, although perennial, is most often planted as a short term autumn annual while it is already blooming or is just about to bloom. It rarely gets a second chance if it finishes bloom before winter. Alyssum and nasturtium can be both warm and cool season annuals. They only gets replanted this time of year because individual plants perform through one season or the other, but probably not both. Nasturtium should be grown from seed.

Annuals Come And Annuals Go

71025thumbJust like warm season vegetable plants in the vegetable garden, flowering warm season annuals get replaced this time of year. Although the weather is still warm, cool season annuals should be planted now so they can disperse roots before the weather gets too much cooler. Except for a few short term annuals and perennials, most should perform until the weather gets warm next spring.

Pansy, viola, Iceland poppy, sweet William, calendula, stock and the various primroses should get down to the business of blooming rather efficiently, and hopefully compensate for the removal of deteriorating warm season annuals. Ornamental cabbage and kale, as well as cyclamen, can be a bit later because they are a bit more sensitive to warmth, but not slowed much by cool weather.

Nasturtium and alyssum can work as either or both warm and cool season annuals. Both are annuals, so individual plants do not last more than a few months. In hot spots, they may perform well in winter, but then get roasted in summer. In cold spots, they may do exactly the opposite. In the right situations, they self sow and bloom all year. Tired old plants should be groomed out if unsightly.

Chrysanthemums are the most prominent of seasonal color for autumn, and come in all sorts of colors that are ideal for an autumn palette. They are actually perennials that are grown as annuals. Unfortunately, they are usually grown as very short term annuals, that are allowed to bloom only once, and then replaced with something more wintry, like cyclamen or ornamental cabbage or kale.

Like cool season vegetable plants, most flowering cool season annuals should be planted as small plants in cell packs. Chrysanthemum, as well as cyclamen and ornamental cabbage and kale that get planted afterward, are the exceptions that should be planted as four inch potted plants, but they are expensive anyway. Primroses can be planted from either cell packs or four inch pots. (Primroses can cause a serious skin allergy, just from contact.) Nasturtium and alyssum should be grown from seed sown early.