Get Perennials Ready For Winter

81212thumbDilemmas are common in gardening. Should summer vegetables that are still producing be removed so that winter vegetables can get started on time? What about replacing summer annuals that are still blooming with winter annuals, and then replacing winter annuals with summer annuals half a year later? Should tender perennials be regarded as annuals, or get a second chance?

Right now, some perennials are looking tired. Many will be going dormant for winter. Many do not get much down time, and will start to develop new growth faster than old growth deteriorates. Not many make their intentions obvious. Deciding how to work with them can be confusing at times. It might take a few years and a few mistakes to get familiar with the habits and lifestyles of some.

If cut back too early, hardy zonal geraniums will not regenerate much until the weather gets warmer at the end of winter. In the interim, they are more likely to be killed by frost without the protection provided by old growth However, some varieties start to grow in winter. If not cut back soon enough, new growth mingles with old, so that they are difficult to separate when they do get cut back.

It is best to observe what hardy geraniums are up to before deciding on when to prune. If they start to develop vigorous new growth down near the ground, the old growth should probably be cut down as far as the new growth. It is likely better to take a chance that they might be damaged by frost. Those that do not start to grow right away can enjoy the insulation of old foliage for a while.

Thoroughly deciduous perennials, like deciduous daylilies, dahlias and some ferns, can be groomed of their deteriorated old growth without risk that they will start to regenerate new growth prematurely. However, cutting back some specie of salvia might actually stimulate development of exposed and frost sensitive new growth. Perennials that get damaged by frost later In winter should not be groomed of damaged growth right away. The damaged material provides a bit of insulation for lower growth, particularly if new growth was stimulated by the damage.

Take It Slowly In Autumn

81010thumbNo more fertilizer! . . . almost. The main exception is turf that might need a bit of fertilizer if it must stay green through the coldest part of winter, but that is another topic for later. Otherwise, most plants start to go dormant through autumn, and should be as dormant as they get by the middle of winter. Fertilizer later than now could be as logical as espresso just before trying to get to sleep.

Keeping marginally frost sensitive plants up past their bedtime can have serious consequences. Lemon trees are not often damaged by frost in the mild winter weather here. That is because they stop growing through late summer, and the last of their new foliage matures before autumn. Fertilizer applied too late can stimulate late new growth, which is more likely to be damaged by frost.

Plants that like a last application of fertilizer as late as the end of September, such as roses, use it for their last minute preparations for dormancy. It actually takes a bit of effort to abscise (shed) foliage. Besides, healthy foliage is easier to abscise than distressed foliage is. Well fed roots, although significantly subdued by dormancy, work later into winter, and get an earlier start in spring.

Roses are, of course, not as likely to be damaged by late application of fertilizer as lemon trees are. They know better than lemon trees do about what to do when the weather gets cool. They just go dormant. Much of the extra nutrients get ignored as they leach through the soil with winter rain. Many of the nutrients become insoluble and unavailable to plants as winter weather gets cooler.

Autumn is the season for allowing most plants to slow down and get ready for winter dormancy. Trying to get them to be as green and productive as they were in spring can do more harm than good. Only plants that are active through winter, such as cool season vegetables, cool season annuals, and some types of turf, might appreciate moderate applications of fertilizer. If newly installed plants want fertilizer, they should get only enough to keep them happy until they get more next spring.

Summer Deciduous

P80623K+++That is a term that we do not hear much. There are not many plants that it applies to. Cyclamen is one of the more familiar plants that is summer deciduous. It is from a climate with reasonably mild winters and unpleasantly dry and warm summers. Just like most deciduous plants are dormant through winter to avoid the unpleasantries of the weather, cyclamen defoliates as the weather gets warm in early summer to avoid the expected heat and aridity. It somehow knows how to stay dormant until the weather starts to get cooler in autumn, and is ready to regenerate new foliage and bloom as the rain starts. The active growing season is through autumn, winter and into spring. It is all a matter of taking advantage of the weather while it can, and avoiding the discomforts of severe weather when necessary.

Rhody, like most dogs, has been shedding his fluffier inner winter coat through spring. He still seems to be too fluffy for the weather, but he must know what he is doing. The remaining wiry outer coat provides a bit of shade, and helps to dissipate a bit of warmth when necessary.

Unlike Rhody, I do not have a fluffier undercoat to shed. All that I could do is shed some of the sparse and wiry outer coat. It might have provided shade, but also interfered with cooling air circulation. It does not seem to be designed to dissipate heat like Rhody’s is. Regardless, it was shed just before the Summer Solstice, and will not regenerate until autumn. A barber sheared back the upper evergreen growth first. I then pollarded most of the lower growth, leaving only a pair of formally shorn hedges flanking the upper margin. They too may be removed soon. Antithetically of https://tonytomeo.wordpress.com/2018/01/17/winter-coat/P80623KP80623K+P80623K++

Bulbs Are Not Finished Yet

41015thumbIt might seem creepy to think about what spring bulbs are doing right now out in the garden. Like victims of a horror movie, they were buried in shallow graves last autumn. They were not dead though. They were undead but merely dormant. While no one can see what they are up to, they disperse roots and begin to push new foliage up to the surface of the soil. Some might bloom soon.

Now it is getting to be time for summer bulbs. Unlike spring bulbs, summer bulbs do not prefer to hang out in the garden through the cool and rainy weather of winter. If planted too early, they can start to grow prematurely, and could potentially get damaged by frost. If planted much too late after winter rain, they will need to be watered more carefully while young, and are likely to bloom late.

Just like spring bulbs, most summer bulbs are really corms, rhizomes, tubers or tuberous roots. Only a few are actual bulbs. Although they are very different physiologically, they perform the same function. They store resources from a previous season through dormancy in order to sustain growth for the next season. Some summer bulbs bloom more than once annually or with many blooms.

Dahlia, canna, crocosmia, hardy orchid (Bletilla) and the old fashioned big white calla are some of the easier to grow summer bulbs. Dahlia is the most colorful, but blooms late in summer or early autumn, and might only perform well for a single summer. With regular watering, canna can grow like a big weed, but in a nice way. The others can grow well enough to get invasive over the years.

Gladiolus and lily will probably bloom for only one summer, but are so colorful that those who enjoy them do not mind. Tuberous begonia is fussier, so is usually grown in pots. Allium, astilbe and maybe liatris have potential to thrive and multiply in the right conditions, but more often bloom for only a few years. Small colored callas are unpredictable too. They are showy but rarely prolific.

After bloom, deteriorating flowers should be pruned away to conserve resources while lingering foliage recharges bulbs for the next winter. This process is known as ‘deadheading’. Gladiolus, lily and any others bulbs that bloom only once obviously need to be deadheaded only once. Dahlia, canna and others that bloom over an extended season will want to be deadheaded a few times.

Winter Is The Season For Pruning

71213thumbNow that winter is only two weeks away, and many deciduous plants are defoliating and dormant, it may seem as if there will be less work to do in the garden. After all, not much is growing. The funny thing is that this is the best time to sneak up on some of them, and prune them while they are sleeping. Depending on what is in the garden, winter can be just as busy as any other season.

There are a few things that should most certainly not be pruned in winter. Maples and birches should either be pruned before or after winter. They bleed profusely if pruned in winter. Plants that bloom in winter or early spring should be pruned after they have finished blooming. Pruning forsythias, flowering cherries and flowering crabapples earlier will remove much of the blooming stems.

Deciduous fruit trees are of course an exception to that rule. They require annual winter pruning so that they to do not produce too much fruit. Excessive fruit is of inferior quality, and can break limbs. It is acceptable when pruning fruit trees to leave a few unpruned stems to cut and bring in later, as long as they are not forgotten. They can be less refined alternatives to flowering cherries.

Once we determine what should not be pruned in winter, it is easier to see that most deciduous plants should be pruned while bare in winter. Elm, oak, poplar, willow, mulberry, pistache, gingko, crepe myrtle and most popular deciduous trees are sound asleep and unaware of what might happen to them for the next few months. They would be pleased to wake already pruned next spring.

Some evergreen plants should probably be pruned as well. Tristania, redwood, podocarpus, Carolina cherry, bottlebrush and the various eucalypti would prefer to be pruned while the weather is cool. Conifers bleed less this time of year; and pine and cypress are less susceptible to pathogens that are attracted to wounds during warm weather. Avocados and citrus, particularly lemons, should not be pruned in winter, because pruning stimulates new growth which is more sensitive to frost.

Plant Spring Bulbs In Autumn

71115thumbOf all the gardening chores, planting dormant bulbs is probably the least gratifying. All we do is dig a hole to the required depth and width, set a few unimpressively dormant bulbs with the correct orientation and spacing, and then fill the hole with the same soil that was removed from it. The process gets repeated until all the bulbs are planted. Soil amendment and fertilizer might be added.

There is nothing to show for our efforts. When finished, only bare soil remains. We might want to plants flowering annuals or a light duty ground cover over the bulbs, or we might just spread mulch. If soil amendment is needed, it should be mixed into the soil at the bottom of the planting holes. Fertilizer can get dispersed over the surface of the soil after planting. There really is not much to it.

Planting bulbs is also a chore that is easy to forget about until it is too late. If we do not see them in nurseries, we might not think about daffodil, narcissus, hyacinth, grape hyacinth, freesia, tulip, crocus, lily, anemone, ranunculus, iris or other spring bulbs until we see them blooming next spring. Yet, this is when their dormant bulbs, corms, rhizomes, tubers and tuberous roots get planted.

Many types of bulbs become available in nurseries at the same time, and can be planted as soon as they become available. It might be too early to plant those that are not yet available. Gladiola, dahlia, allium, calla and canna are summer bulbs that will become available later because they likely should get planted later, although calla and canna do not seem to care when they get planted.

Daffodil, narcissus and grape hyacinth are probably the most reliable spring bulbs for naturalizing. Bearded iris is likewise very reliable, but needs to be dug, split and groomed every few years. Freesia and crocus may not naturalize as reliably. Lily, tulip, anemone, ranunculus and hyacinth are spectacular in spring, but are unlikely to naturalize because they prefer more of a chill in winter.

Some bulbs can be phased in their first year. For example, if freesia flowers are expected to last about a week, a second group of bulbs can be planted about a week after the first. A third group can be planted about a week after the second, and so on for a few weeks until the planting season ends. As the first group finishes bloom in spring, the second group begins to bloom, and so on.