Mandevilla
Young plants of Mandevilla are extremely sensitive to handling and environmental factors. Once established, they become robust growers in warm weather, but not without some demanding cultural attention.
On arrival, place liners under a 30 to 50% shade and water thoroughly. Plant as soon as possible into light, well drained potting mix. Peat based mixes with 30% pine bark and 15 to 20% of inert components (saw dust, sand, airlite, perlite, etc.) are recommended. The pH of the soil should not be higher than 5.8-6.0. Caution: Significant root damage can occur when dislodging plants from liner trays and during planting. To remove plants from trays with minimal root damage, hold the top of the plant while pushing the soil ball up from the bottom of the tray then applying gentle upward pressure on the top. While planting, do not press liners into potting soil. Instruct your planters to handle the liners gently and to plant in cavities and gently cover. Tight or compressed soil surrounding the newly planted liner can restrict root growth and reduce drainage causing root rots. Plants should be watered in thoroughly soon after planting.
The most critical step to success after planting is to have a strict water management program. Young plants should not be allowed to dry out during first 14 to 21 days after planting. Adequate moisture is not only critical to young plant growth and establishment, but will also reduce stress resulting from the interfacing of the liner and container media. During the first fourteen days, we recommend watering every day. If in doubt about watering or if it only “looks like rain,” water.
Upon second watering, while soil is still moist, drench plants preventively against root rot with fungicides*: Cleary’s WP or Banrot against Fusarium, Subdue against Pythium and Phytophthora or use Rootshield. As plants mature, the urea and ammoniacal forms of Nitrogen (N) is the most preferable. Incorporate 18-6-8 as the primary source of nutrients. Also, applications of fertilizers with high levels of phosphorous (9-45-15, 10-52-10) have a positive effect on growth of young plants. If necessary, top-dress with 16-6-10 to finish the crop.
Many of the newer Mandevilla cultivars available today show significantly better tolerance to common leaf spot diseases such as Anthracnose and can require less frequent applications of pesticides. Selecting full sun growing areas with good drainage and good air movement are helpful. Preventive sprays to safeguard against the spread of Anthracnose may be needed. Recommended fungicides to use on an alternating basis are Daconil, Cleary’s, Dithane, Kocide, Junction, Spectro 90, Pageant and Zyban. To deter nematodes, grow off ground or on blocks.
Insects to scout for are: thrips, aphids, spider mites, mealy bugs and particularly white flies, which can be persistent and require regimented spray programs. Following are recommended insecticides*: Thiodan, Sanmite, Talstar, Flagship, Safari, Avid, Orthene (Turf, Tree & Ornamentals), Mavrik, Conserve EC, TriStar, Enstar, Marathon, Suffoil and M-Pede. Recommended miticides include: Sultan, Floramite, Hexygon and Ovation.
*This text is a recommendation only; it is not an endorsement of any products or acceptance of any liability as a result of usage. Always conduct small tests with your plants under your unique conditions before implementing pesticide spray programs.
Updated: January 8, 2016. Copyright Oglesby Plants International, Inc. 2010-2016