Care and Maintenance of  Ornamental Plants

By Simrat Singh and 

Rishu Sharma

Punjab State has a rich diversity of ornamental plants that are utilized for the beautification of outdoor and indoor landscapes. The woody perennials endure harsh climatic conditions in outdoor weather and they may exhibit seasonal phenological changes. An avenue of Lagerstroemia speciosa presents a picturesque landscape by exhibiting different hues of leaf color. Likewise, the bright pink color flowers of Chorisia speciosa looks majestic amid leafless condition in winter.  The colorful bracts of Poinsettia and Bougainvillea present a scenic view of the garden landscape. Climber plants such as Golden shower and Clerodendrum splendens adorn the bare walls of city landscapes.  However, the cold climate makes the landscape look barren due to leaf fall in several of the deciduous woody perennials. The heart of the landscape ‘Lawn’ also turns brown and patchy due to the dormant nature of warm-season grasses. The scarcity of space in urban areas has encouraged the use of potted ornamental plants for the beautification of indoor landscapes such as balconies, window sills, patios, etc. However, the charm of keeping these indoor plants presents numerous challenges for the house owner during winter, especially when the temperatures drop to near the freezing point. Most of the potted foliage and flowering ornamentals exhibit symptoms of winter injury upon exposure to cold weather.  The leaves of potted foliage plants may turn yellow to brownish in color due to frost injury. Plants such as Syngonium, Aglaonema and Coleus began to change leaf color and may also shed leaves upon exposure to freezing temperatures even for a few hours.  

The maintenance of woody perennials and potted ornamentals during winter requires certain considerations to be taken care of by homeowners and garden landscape managers. Following the below-mentioned care and maintenance guidelines, the beauty of the indoor and outdoor winter landscapes can be sustained and enjoyed.

No.1 Placement

It is imperative to place the plants in different locations of the house as per their light requirement. For instance, higher light requiring plants should be kept near the windows receiving bright indirect light and low light requiring plants can be kept at corners receiving diffused light. The foliage plants must be exposed to winter sun for a few hours by shifting those in a well-ventilated place. Also, the sensitive plants should be protected from frost injury during nighttime by shifting these under a roof or sort of enclosure. The potted indoor plants should be rotated weekly with those kept outside to maintain the vigor and luster of leaves.   

No. 2 Covering and Mulching

It is crucial to protect the newly planted woody perennials from the harsh winters by erecting ‘kullies’ made with paddy straw ensuring sufficient sun exposure from the south and west directions. The berms alongside the trees and shrubs should be mulched with paddy straw up to a thickness of 4-6 inches to check the weed growth and regulate the soil temperature (see figure).  The microclimate variation provided by the mulch helps the newly planted woody plants to sustain their growth in the harsh cold weather.  

No. 3 Pruning and grooming

The woody deciduous perennials may be correctively pruned by selectively removing dense crisscrossed and dried branches to ensure adequate penetration of sunlight and aeration within the tree canopy and the plants underneath. It is advisable to make a sharp and clean cut and cover the exposed portion of pruned branches with a suitable copper-based fungicidal paste such as Blitox (50% WP formulation of Copper Oxychloride) mixed with linseed oil to avoid the drying of exposed tissue and prevent disease infestation. The indoor potted plants should be effectively groomed by carefully removing dead, pale, drying and diseased leaves. The shriveled flowers of Korean types of chrysanthemums should be periodically removed to enhance the presentable quality of pots. 

No. 4 Manuring

Woody landscape plants should be fertilized with organic manures during dormant conditions. The well-decomposed farm yard manure and vermicompost (at the rate of 5 kg and 1 Kg per meter square respectively) should be applied alongside the berms of trees and shrubs, followed by light hoeing and irrigation. The potted foliage ornamental plants must be fertilized annually during winters, by replenishing 2-3 inches of the surface soil with an equivalent amount of above organic manures. Care should be taken to add only well-decomposed organic manures to avoid root rotting of plants.

No. 5 Irrigation

It is advisable to provide light irrigation to woody perennials in public parks and home gardens to regulate the soil temperatures during an event of frost. The irrigation frequency may be regulated as per the prevailing weather, soil moisture and plant requirement. In potted plants, watering can be done based on leaf vigor and moisture in the growing media that can be assessed by visualizing the soil texture and finger test method. Stick the index figure one-half inch deep into the potting soil, if the finger comes clean without any soil particles and feels relatively dry, it is time to irrigate the pots.  

Other considerations to take care of ornamental plants and garden landscapes during winter:

I. Collect all the leaf debris and make a compost heap

II. Plan and create a layout for the plantation of saplings of deciduous trees and shrubs

III. Planting of bare-rooted rose plant saplings in well-prepared rose beds

IV. Rouging out weeds from flower beds of annuals and irrigate as per need 

V. Provide stakes for supporting dahlias in pots and beds 

VI. Plant hardwood cuttings of dormant woody shrubs

VII. Appropriate time for raising nursery of summer season marigolds under poly sheet cover

Punchline:  It is important to carefully look for any unusual symptoms appearing in the foliage of indoor and outdoor ornamental plants. These are the distress signs that call for immediate attention for their appropriate placement, and adequate cover to avoid winter chilling. 

Writers are from the Department of Floriculture and Landscaping, PAU, Ludhiana