Buddleja davidii pink delight is a shrub that typically grows to 6-8 feet tall and wide. It is a deciduous shrub with ovate to lanceolate, toothed leaves that are greenish-gray in color. The fragrant flowers are pink and bloom in summer.
Related plant:
Buddleja Davidii Nanho Blue
Related plant:
Buddleja Asiatica
About soil condition, Buddleja davidii 'Pink Delight' prefers well-drained soils, yet is quite tolerant of poorer soils and will even grow in heavy clay soils. It is not fussy about soil pH, but does best in full sun.
Similar to other Buddleja species, Buddleja davidii pink delight requires full sun to grow and bloom optimally. However, it is more tolerant of partial sun than some other species. It will still bloom in partial sun, but the blooms will be less abundant. If you live in an area with hot summers, you may want to give this plant some afternoon shade to protect it from the heat.
The temperature condition for Buddleja davidii pink delight is optimum at 68 degrees Fahrenheit. Below this, the plants will not bloom as well. However, they are still able to tolerate temperatures as low as 50 degrees Fahrenheit.
Ideal humidity condition for this plant is around 50% Buddleja davidii 'Pink Delight' is a fast-growing, deciduous shrub with an upright, arching habit. It can grow up to 6 feet tall and 8 feet wide. The leaves are dark green and lance-shaped, with a silver-gray underside. The flowers are pink, tubular-shaped blooms that appear in midsummer and attract butterflies. This plant prefers full sun and well-drained soils. It is tolerant of drought and salt spray. Deadhead spent flower heads to encourage reblooming.
Discussing fertilizer, this family of plant requires little to no fertilizer and too much will actually damage the plant. They are drought tolerant, but will not survive if the soil is constantly wet. The best way to determine if they need water is to stick your finger in the soil up to the first knuckle. If the soil is dry, they need water.
Pruning your Buddleja davidii Pink Delight is an important part of plant care. This plant can become leggy and overgrown if not pruned regularly. Pruning also encourages new growth and keeps the plant looking its best. To prune, simply cut back any overgrown or leggy stems to the desired length. New growth will quickly fill in any bare areas.
Propagation of Buddleja davidii 'Pink Delight' is easy by seed or semi-ripe cuttings in late spring or early summer. Sow seed on the surface of a well drained seed sowing mix and gently firm down. Place in a propagator or seal inside a clear polythene bag at a temperature of 18-21C until after germination which usually takes 21-60 days. Alternatively, take semi-ripe cuttings in late spring or early summer. Cuttings should be taken from new growth that has hardened off, and be around 10-12cm long. Use a sharp knife or secateurs and take a slanting cut just below a node. Remove the bottom leaves and insert the cuttings around the edge of a 9cm pot filled with moistened cutting compost. Cover with a clear plastic bag or propagator lid and place in a bright, warm place out of direct sunlight. Keep the compost moist but not wet and roots should form within 3-4 weeks at which point the cuttings can be potted on into 7.5-10cm pots and grown on under glass.
Usually, the plant growth rate issues are due to environmental conditions. A lack of sunlight is the main cause for a lack of growth. If your plant is not getting enough sun, try moving it to a location that receives more sunlight. Another common cause of slow growth is too much water. If you think your plant is getting too much water, try letting the soil dry out between watering.
Common problems for this kind of plant are usually due to over-watering, but it can also be caused by pests, diseases, or nutrient deficiencies. Over-watering can lead to root rot, which can kill the plant. Pests such as aphids, whiteflies, and scale can infest the plant and cause damage. Diseases such as powdery mildew or botrytis can also cause problems. Nutrient deficiencies can cause the leaves to turn yellow or brown and the plant may not flower properly.
Source:
PlantFacts - Ohio State University
Butterfly bush : Buddleja davidii - Buddlejaceae (Butterfly-bush)
Buddleja davidii (Buddlejaceae) - HEAR species info