Calla For 3 Gallon Pot (6" or 1 gallon pot instructions below)
Aethiopica are moisture loving. Use a well draining media with a pH of 5.5-6.5 that is high in organic matter. Plant 2" deep in containers or 3-4" deep in beds.
Aethiopica will withstand a wide range of light conditions (500 to 5,000 candles). Higher light can be tolerated in cool and humid periods.
Plants can handle full sun to 70% shade without becoming too badly stressed, but 50% shade is ideal. Deeply shaded conditions will cause lengthened, but weakened stems
Aethiopica tolerate a range of temperatures but prefers relatively cool temperatures. Optimum daytime temperatures are 55-65⁰F; nighttime 45-55⁰F; germination at 65-70⁰F until sprouting helps hasten rooting and establishment. Cool nights with clear days will promote shorter, stronger stems. Aethiopica are somewhat frost sensitive. Foliage will not withstand prolonged freezing temperatures. Bulbs can take some frost but not soil freeze to bulb depth.
Keep soil slightly moist until substantial sprouts emerge. Then keep soil slightly moist (but not soggy) until peak bloom then decrease moderately.
Proper fertility is critical for full plant growth with well-colored leaves and continued flower production in Aethiopica. Use a soil incorporated 30-day release preplant charge of nitrogen and potassium (containing little or no phosphorous). This will produce good early establishment of roots and improved early vigor. At approximately 3-4 weeks, begin a semi-balanced liquid feed @ 200 ppm weekly or 100 ppm constant using 20-10-20 or initially as needed. Modifications can then be made based on individual growth objectives and conditions. At leaf unfurling, reducing to 50 ppm alternated 1:1 with clear water will keep plants from getting too leafy. Alternately, consider the use of a low phosphorous fertilizer (i.e. 17-5-17) can result in better plant balance.
Generally it is best to make a single PGR drench application when plants are at 1/2 to 3/4 desired plant height. Note that the require rate will depend primarily on the light, temperature, fertility and your bulb size & form. It’s often best to use apply Bonzi at 7.5-10 ppm @ 0.25-0.33oz/gal (2-2.6ml/L). 3.75-7.5 ppm @ 0.125-0.25oz/gal (1-2ml/L) should be used if: 1) lighter desired effects are desired; 2) earlier or multiple applications will be use; 3) smaller and/or clustered bulbs are being used. TOO HIGH A RATE OR TOO EARLY AN APPLICATION CAN CAUSE LEAF CRINKLING, PLANT ROSETTING, LACK OF BLOOM OR GENERAL STUNTING. If plants become over growth regulated, a GA rescue spray can be effective @100-200ppm GA3 or GA4+7 [and coupled with a mild surfactant]. *Bonzi rates higher than 10 ppm may arrest plant height completely.
Disease Prevention & Control
Aethiopica is generally susceptible to three (3) primary soil borne pathogens: Pythium & Phytophthora (“water molds”) plus Rhizoctonia and bacteria: Erwinia (Pectobacteria spp.). “Water molds” are often the first & most critical component in the disease complex, followed by Rhizoctonia. with the following preferred materials:
Once root injury occurs, Erwinia will often enter as a seconday infection. Our best tank mixed, four-part chemical drench targets the “3-pathogen complex”
1) WATER MOLD part 1- Subdue Maxx (mefenoxam 25.1% ai) @ 0.5-1oz/100 gal (4-8ml/100 L)
2) WATER MOLD part 2- Aliette (fosetyl-aluminum 80% ai) @ 13oz/100 gal (98gm/100 L)
3) RHIZOCTONIA- Heritage (azoxystrobin 50% ai) @ 4oz/100 gal (30gm/100 L)
4) ERWINIA- Agrimycin-17 (streptomycin sulfate 21.2% ai) @ 8-16oz/100 gal (60-120gm/100 L)
Pesticide drench timing is critical. Drench within the first 2-3 days of initial watering . Timing of the second drench should be made at 14 to 21 days. A third drench may be necessary 3-6 weeks after the second one (5-9 weeks from planting). *Always drench in the mornings or early enough for all foliage/runoff to dry thoroughly. Watch for leaf spot as leaves unfurl. Once leaf spot is observed, spray foliage to runoff with a selection of the following:
1) BACTERIAL LEAF SPOT part 1- Champ II (copper hydroxide 37.5%) @ 32-64oz/100 gal (240- 479ml/100 L
2) BACTERIAL LEAF SPOT part 2- Dithane (mancozeb 75%) @ 32oz/100 gal (24 ml/100 L)
3) FUNGAL LEAF SPOT option 1- Daconil Weather Stik (chlorothalonil @ 54%) @ 22oz/100 gal (165ml/100 L) option 2- Chipco 26019 26GT (iprodione @ 23.3%) @ 32oz/100 gal (240 ml/100 L) *DO NOT COMBINE FOLIAR COPPERS WITH ALIETTE OR OTHER ACIDIFYING PRODUCTS.
Inspect Crop Weekly. Routinely scout for cleared or browning roots, leaf spots, etc. • ALWAYS WATCH FOR ERWINIA INFECTED PLANTS TO CAREFULLYROGUE & DISCARD. Re-drench per recommendations if root problems are discovered, up to a total of three times over the life cycle. Sanitation is critical, especially in multiple cropping programs where rot can progress without an obvious cause. Sanitize benches, floors, conveyors, pots, soil mixers, etc. between crops.
Control Fungus Gnats and Shoreflies due to their ability to spread bacteria and other diseases. Control white flies, aphids and thrips on an as-needed basis.If aphid or thrips are present, use aggressive control measures since they are capable of rapidly spreading various viruses. Watch for early leaf chewing evidence from larvae after sprouting. Most materials can safely be applied at label rates; beware of chemical incompatibilities described on label(s).
Calla for 6" or 1 gallon pots
Storage After Arrival
Unpack on arrival. Dispose of any soft rot and wash hands to avoid spreading the bacterial to healthy bulbs. Place in well ventilated trays at 65° F for a couple of days prior to planting. This will insure any possible friction wounds caused by transit are well callused before planting. For long-term storage (6 weeks or more) keep well ventilated at 45° F and a relative humidity of 80%.
Plant with 1 to 1 1/2" of medium over the tuber, rounded side down, sprouts (eyes) up. Pot sizes below 4 1/2" standard are more difficult to grow due to root volume restrictions (especially in clay pots). Suggested planting guide is one bulb per 4 1/2" pot and 2 bulbs per 6 1/4" pot. Additional care and management of fertility and irrigation are required in small or shallow pots because plants tend to be weaker, more easily stressed and, therefore more disease prone. The medium should be well drained, a pH of 6 - 6.5 and have good air porosity (optimal at 20% +/- 5%).
Water management is critical. Keep pots moist but avoid excessively wet and excessively dry conditions. The first (within 2 days of planting) thorough watering should be a three-part preventative chemical drench. Then water sparingly until leaves unfurl. In week 3 or 4 reinoculate with a drench of Trichoderma and then a week later do a second chemical drench. Schedule these drenches to coincide with required watering to avoid overly wet pots.
Calla can be exposed to full sunlight, unless the temperature in the greenhouse goes over 80° F, then some shading is recommended to avoid leafburn.
Early fertility levels in calla, at the time of planting and extending two weeks, enhances overall long-term plant fullness and uniformity of vigor. A 10-20 day media incorporated pre-charge of nitrogen and potassium (no phosphorous in early pots) would be ideal.
Market your pots with slightly less than one half the total number of expected blooms showing color or in spike. Ship long distances under refrigerated conditions (approximately 40° F or 5° C) to avoid excessive stretching. Retail under cool and bright conditions.