The ‘Excel’ Lilac, formally known as Syringa x hyacinthiflora ‘Excel’, is a valued shrub renowned for its early and abundant blooms. This hybrid variety offers vigorous growth and a delightful fragrance, making it a popular choice for gardeners seeking to enhance their landscape with vibrant spring color. Its appeal lies in its ability to deliver a showy display of flowers, often signaling the start of the lilac season. The ‘Excel’ Lilac is a low-maintenance option that brings beauty and scent to various garden settings.
Understanding Excel Lilac
The ‘Excel’ Lilac presents a striking appearance with its upright, deciduous growth habit. It features showy panicles of fragrant, single, lilac-lavender flowers that emerge in mid-spring, typically blooming about 7 to 10 days earlier than more common lilac varieties. These abundant blossoms release a strong, sweet scent, filling the air with a classic springtime aroma. The plant’s erect, open branches are adorned with fresh green, heart-shaped leaves throughout the growing season, which transition to attractive burgundy or bronze hues in the fall.
This lilac cultivar reaches a mature size of approximately 8 to 10 feet in both height and width. Its robust nature allows it to thrive in a range of climates, demonstrating hardiness in USDA Zones 2 through 7. A notable characteristic of the ‘Excel’ Lilac is its superior heat tolerance compared to many other lilac types, attributed to its lower chilling requirement. This adaptability makes it a suitable choice for warmer regions where other lilacs might struggle.
Planting Excel Lilac
Successful establishment of an ‘Excel’ Lilac begins with selecting the optimal planting time, ideally in early spring or during the fall. The chosen site should receive full sunlight, meaning at least six hours of direct sun daily, to ensure prolific flower production. Good air circulation around the plant is also beneficial.
‘Excel’ Lilacs thrive in fertile, humus-rich, well-drained soils, preferring an alkaline to neutral pH, typically ranging from 6.5 to 7.0. Before planting, loosen the soil to a depth of 12 to 18 inches and incorporate organic matter, such as compost, to improve its structure and nutrient content. Dig a planting hole that is twice as wide as the root ball and deep enough so the top of the root ball sits level with the surrounding soil surface.
After carefully removing the plant from its container, position it in the prepared hole, then backfill with soil, gently tamping it down to eliminate air pockets. A thorough and deep watering immediately after planting helps to settle the soil around the roots. Applying a 2 to 3-inch layer of mulch around the base of the plant can help retain soil moisture and suppress weeds, taking care to keep the mulch a few inches away from the trunk.
Caring for Excel Lilac
Maintaining an ‘Excel’ Lilac involves consistent watering, especially during its first growing season, to ensure roots become well-established. Once mature, these plants are resilient and typically require supplemental watering only during extended dry periods, aiming for about one inch of water per week. Watering deeply at the soil level, rather than overhead, helps to prevent foliage diseases.
Fertilization is not always necessary for ‘Excel’ Lilacs, particularly if planted in rich soil. If soil nutrients are lacking, a granular, balanced fertilizer with a lower nitrogen content, such as a 10-10-10 or 5-10-10 ratio, can be applied in late winter or early spring. Excessive nitrogen can promote leafy growth at the expense of flower production. Incorporating a layer of compost around the plant annually also provides beneficial nutrients.
Pruning is an important aspect of care and should be done immediately after the plant has finished flowering, as ‘Excel’ Lilac blooms on old wood. Prompt removal of faded flowers, known as deadheading, helps redirect the plant’s energy towards developing more blooms. Regularly removing any suckers that emerge from the base of the plant helps to maintain its shape and prevents unwanted spread. For older, overgrown plants, thinning out up to one-third of the oldest canes can rejuvenate the shrub and encourage new growth.
Common Issues
While ‘Excel’ Lilacs are generally robust, they can occasionally encounter specific pests and diseases. Common insect concerns include leaf-mining moths and thrips. The lilac borer, a clearwing moth larva, can bore into stems, potentially causing branch dieback. Scale insects may appear as small, waxy growths on stems. Pruning out affected branches can manage borers, while scale can be addressed with horticultural oils or by physically removing infested sections.
Among diseases, powdery mildew is a frequently observed fungal issue, appearing as white, powdery spots on leaves. Although often unsightly, powdery mildew is primarily an aesthetic concern. ‘Excel’ Lilac is noted for its disease tolerance and often exhibits resistance to powdery mildew compared to common lilacs. Ensuring good air circulation and planting in full sun can help mitigate its occurrence.
Bacterial blight, caused by Pseudomonas syringae, can manifest as blackening of new shoots, distorted leaves, and brown spots with yellow margins. This bacterial disease is spread by wind and rain. Promptly pruning out affected plant material, ensuring cuts are made into healthy wood, can help control its spread. Fungal leaf spots may also appear as brown spots on leaves; these are cosmetic and can be managed by removing infected leaves and promoting air circulation.