Gardening is not always fun. After diligently tending to warm season vegetables through spring and summer, it eventually becomes necessary to pull them up to relinquish space for cool season vegetables that grow through autumn and winter. It likely would be less unpleasant to wait for them to succumb to frost, but by that time, it would be getting late for the incoming vegetable plants.
Removing warm season annuals and bedding plants is just as necessary, and might be just as unpleasant. The only consolation is that the incoming cool season annuals and bedding plants are likely to be blooming well as they get installed. Even though they take a while to mature, there is no time without at least some degree of color. Warm season annuals may be tired by now anyway.
Just like cool season vegetable plants, the various cool season annuals and bedding plants appreciate an early start so that they can begin to disperse roots while the soil is still somewhat warm. Only those that dislike warmth should wait. Cyclamen and flowering cabbage and kale can be planted as late as winter. Flowering cabbage and kale might even bolt if they get too warm too soon.
Pansy, viola, sweet William, stock, Iceland poppy, calendula and various primroses are all seasonable now. They should be happy to bloom until they too need to be replaced by annuals for the following season, several months later. Chrysanthemum, marigold and a few other autumn annuals are short term annuals that bloom excellently through autumn, but are not likely to bloom later.
Just like most of the cool season vegetables, most of the cool season annuals should be planted as small seedlings in cell pack. Chrysanthemum and many of the primroses, as well as cyclamen and flowering cabbage and kale that come later, should actually be planted as four inch potted plants. Needless to say, some of these are expensive relative to their respectively limited bloom seasons. Seed for nasturtium and alyssum can be sown directly into the garden. Nasturtiums seedlings in cell packs are expensive and do not transplant well.
The common name sounds funny, but it is easier to pronounce then than the Latin name. Mulla mulla, Ptilotus exaltus, is an Australian species that has been locally available longer than its limited popularity suggests. It may seem to be more peculiar than it is because it is grown primarily by specialty growers, who happen to grow many cool plants that should be more popular than they are.
They are really just smaller versions of the larger perennial dahlias that are grown for their big bold flowers and flashy colors. Technically, annual dahlias produce smaller versions of the same perennial roots that can survive through winter to regenerate the following spring. Yet to most of us, it is easier to purchase new plants in spring than to grow new plants from stored roots.
Twice 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.
‘Moonshine’ is probably the epitome of fernleaf yarrow, Achillea filipendulina, even though it is technically a hybrid. From the middle to the end of summer, its three inch wide corymbs (flat-topped trusses) of tiny bright yellow flowers stand as high as three feet above ferny and gray basal foliage. Bloom is best in full sun and warm exposure. Established plants do not need too much water.
Their pastel hues and blends of pink, lavender, near red and white are so perfect for the middle of spring when cosmos, Cosmos bipinnatus, begin to bloom. They are just as perfect as bloom continues right through summer and almost to autumn, when the tall and airy plants finally begin to wear themselves out. If they continue through autumn, they eventually succumb to frost in winter.
Not all annuals last as long as petunias do through summer, or pansies do through winter. Some fill in for the in between seasons, or if longer term annuals do not last quite as long as they should. Cockscomb, Celosia plumosa, blooms best now that it is about halfway through summer, and then finishes as weather gets too cool for it in late autumn, not so much more than two months later.
In only a few years, busy Lizzie, Impatiens walleriana, went from being one of the most popular warm season annuals to being unavailable in nurseries. It is now making a slight comeback. Most of those planted during their planting season last spring are now so profuse with bloom that their rich foliage is mostly obscured. Although they can be perennial, almost all get replaced in autumn.