John M. Englert
Natural Resources Conservation Service - Norman A. Berg National Plant Materials Center
Bldg. 509, BARC - East, E. Beaver Dam Road
Beltsville, Maryland 20705
|Family Scientific Name:
|Family Common Name:
||Late purple aster
||Cumberland Gap National Historical Park
||Massachusetts and New Hampshire to Missouri and Kansas and south to Florida and Texas. Found in woods and dry open places.
|Time To Grow:
||Stock Type: container plugs.
Height: 4-6” at outplanting after cutbacks.
Root System: Firm full plug; roots fill container.
||Collected in Cumberland Gap, along 25E west of Cudjo Cave by NPMC staff in 11/92; harvested from NPMC seed production block in 1998, 1999 and 2000.
||Seed Processing: For aster species that are grown in NPMC production fields, seed is harvested with a modified Trac-Vac which removes only the seed with pappus from the stem. Seed may also be harvested with any other vacuuming process such as a shop vac or modified leaf blower. In cleaning, the pappus is removed from the seed by a debearder modified by NPMC staff for small seed lots. For ease of cleaning, large seed lots are first run through a large clipper before being further refined in a desk top clipper. Either machine will need a solid bottom screen and top screen with holes large enough for the seed to fall through. Fan speed is set low enough to blow only empty seed out. Removing the pappus from the seed of aster sp. reduces the cleaned seed weight by approximately 10 times, and seeding rates have to be adjusted accordingly since seed with pappus may average 240 plugs per gram, while cleaned seed without pappus may average up to 2,000 plugs per gram.
Seeds/Kg: Seed is small. 100 seed weights were .02, .03 and .04g.in three successive years. Estimated at between 2,500,000 to 3,300,000 seeds per Kg.
Purity: Purity of seed harvested from NPMC fields has varied from 40% to 92%.
||Seed Treatments: Seed germinates in light, therefore it should be surface-sown.
|Growing Area Preparation/
Annual Practices for Perennial Crops:
Propagation Environment: Greenhouse with alternating day/night temperatures; daytime temperatures varied from 70-90ºF depending on natural solar; night temperatures averaged around 65-68ºF. Plugs were grown under 14-16 hour long day conditions using high pressure sodium lighting from 4:30-10:30 p.m.
Seed Propagation Method: Seed was hand-sown into germination trays. If seed had pappus still attached it was surface sown over tray cells in small clumps. Cleaned seed without fluff was mixed with talc and surface-sown using a salt shaker.
Container Type and Volume: Seed is started in 392 or 406 germination plug trays. See Sowing Technique for further discussion. Seedlings are transplanted into Ropak Multipots (67 cell) or 72 trays.
Growing Media: seed is sown into germination mix. Seedlings are transplanted into Sunshine #1 (72’s) or #5 (multipots). The potting mix is amended with 18-6-8,180-day Nutricote SR (0.15 lb./cu. ft., or 20 oz. per 3.8 cu. ft. bale of mix).
||Sowing Date: Winter, depending on time of planned outplanting in the spring.
% Emergence and Date: Using the following protocol, most of the seeds that will germinate have done so within 4 to 7 days.
Sowing/Planting Technique: Seed is small and is surface-sown on germination trays. Uniformity of germination is greatly enhanced by keeping seed trays moist and warm. Trays were covered with clear plastic and placed on heat mats set at approximately 75ºF. Using this protocol, seedlings emerged in about 3-5 days, with multiple seedlings in each cell, and the target number of seedlings germinated within a week. We have hesitated to direct-sow aster seed into final containers because cells tend to germinate irregularly or too thickly and there is often uneven growth and maturation of the seedlings. Selecting plugs from the germination trays that are at the same stage of development provides reasonable assurance that contract goals and deadlines will be met. However, since we started using the above seeding protocol, germination occurs much more quickly (in days rather than weeks), with more germination and even growth.
Establishment Phase: Seedlings in germination trays need to be kept evenly moist. We have put trays under mist, but slowing of growth may occur if left too long. Pulling plugs is easier if there are multiple seedlings in each cell and this can be done early. Seedlings seem to grow more rapidly the sooner they are bumped up to plug trays with larger cells, potting media and fertilizer. Thinning of crowded seedlings may be required to allow one seedling to dominate the cell.
|Active Growth Phase:
||Rapid Growth Phase: Transplanted plugs are lightly fertilized approximately bi-weekly, or as needed, with a soluble fertilizer (Technigro 16-17-17 @ about 100 ppm). Cutbacks are performed to keep top growth uniform and strong, to prevent shading of smaller leaves, and to control insect pests and fungus. Foliage does attract typical greenhouse pests (aphids, mites, whiteflies) and cutbacks will eliminate many larval forms. Spot treat with insecticides/miticides as needed.
||Hardening Phase: Approximately 2 weeks prior to outplanting, temperatures are reduced in the green house or plants are moved outdoors to a sheltered location, weather permitting, and fertilization is stopped.
|Harvesting, Storage and Shipping:
||Harvest Date: Seed is harvested in late fall, (November or December). Plugs are outplanted in the spring.
Total Time to Harvest: about 12-14 weeks from germination to finished plug.
Seed storage: Cleaned seed is stored in seed bags in the NPMC cooler at 40ºF, 35% relative humidity. Seed of some aster species has been stored from 1994 and still germinates well.
Storage Conditions: Plugs are grown and planted the same season and have not been over wintered at the NPMC.
|Length of Storage:
|Outplanting performance on typical sites:
||Outplanting Site: CUGA and NPMC. A seed production block was established at NPMC.
Outplanting Date: Spring at the parks, spring or fall in NPMC field production blocks.
||Brown, M. L. and R. G. Brown. 1984. Herbaceous Plants of Maryland. Port City Press, Inc.
|Davis, Kathy M.; Kujawski, Jennifer L. 2001. Propagation protocol for production of container Aster patens plants; Natural Resources Conservation Service - Norman A. Berg National Plant Materials Center, Beltsville, Maryland. In: Native Plant Network. URL: http://www.nativeplantnetwork.org (accessed 26 May 2015). Moscow (ID): University of Idaho, College of Natural Resources, Forest Research Nursery.|