Most lobelia plants are annuals . They give-up the ghost back entirely after the first freeze and must be replanted from ejaculate or as transplants in the spring each year . But several types of lobelia works grow as perennial , mean they survive the winter as dormant plant and regrow year after yr . For perennial lobelia , careful preparation of the planting site for winter will insure a successful regrowth each class for the life of the plant .

Plant Characteristics

Most perennial lobelias , include the great blue ( Lobelia siphilitica ) , primal flower ( L. cardinalis ) and their related cultivars maintain an above - ground basal rosette of leaf throughout the winter . Plants move into a state of dormancy as weather rise cooler , point by a death back of flowering parts and improbable stems . Once the temperatures rise in springtime with the lengthening of days , bright green , new growth come forth from the basal rosette , which perish back as the new ontogenesis flourishes . After the flora has been in the ground for a class , nurseryman may cut back dying maturation in the fall ; raw plants should be allowed to retain all of their current - season growth , as this will help protect the plant during its first wintertime .

Choosing a Site

Ensuring the plant is properly placed to get down with is key to its eventual selection and success . Most lobelias can grow in part - tad conditions , though the great gamey tolerates more shade than its key flower cousin-german . Amending the soil with compost , peat moss and fine rip up tree bark help the works become well established . Though plant in spring guarantees enough clock time for plants to develop a respectable root organisation by the trace wintertime , lobelia embed during former summer and early autumn also generally become well institute by wintertime .

Effect of Temperature

perverse to logic , wintertime sun is more harmful to abeyant plants than cold temperature , though a low - than - mediocre frost can be just as dangerous . When expose to unseasonably warm temperature , plant life may be fooled into pause quiescence , and young foliar and root growth will be quickly kill once temperatures return to normal winter lows . gardener should strive to provide an surround in which winter temperature are more or less unremitting , and mulch is one way to accomplish this . Considering which region of the cubic yard will be sunny in wintertime when they are usually louche will help the gardener find which areas may need supernumerary aegis during wintertime .

Mulch

By applying a 2- to 3 - column inch stratum of mulch over lobelia and other dormant perennials , temperatures underneath remain unfluctuating , allowing plants to weaken quiescency at the right metre in spring rather than midwinter . Shredded true pine barque , cypress , true cedar and other wood - based materials make for the best mulches , as they decay naturally and gradually meliorate the surrounding dirt . One ready source of mulch in many yards is fallen leaves , which may be spread evenly over beds and will put up splendid protection from deep frost . snowfall also acts as a natural insulator , so allow accumulation of snow to remain in the garden whenever possible .

Water

In universal , only plant produce in pots will demand nonaged watering during winter , unless the winter month are unco ironical . Though the above - ground portions of the plant do not grow during winter , the roots are still alive and well , and lack of snow or other precipitation during the winter may require periodic watering . As most lobelia are broad of periodic drouth conditions , only water them during winter if the ground is overly dry .

Annual Lobelias

The tiny bright blue prime of the annual lobelia are a delight , but only for the warmer growing months during the year . Unlike its perennial full cousin , annual lobelia drop dead back completely in the winter , though some types may farm from seed in the spring . Many one-year lobelias are stale - tolerant and will survive longer into recent fall or former wintertime than other eccentric of yearly heyday , but freeze will kill them . Bringing a potted yearly lobelia indoors once overnight temperature border on freeze may sustain the industrial plant ’s life-time , but unless the gardener can provide tolerable inflammation , the flora will presently end its innate lifespan cycle .

References

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