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A survey of commercial nursery growers was conducted to identify cultural practices used in wintercreeper euonymus (Euonymus fortunei) production. Growers that have or have not experienced anthracnose incited by Colletotrichum gloeosporioides on wintercreeper euonymus participated in the survey. Nurseries reported using a variety of practices to produce quality plants for sale. Plant culture appeared similar between nurseries with anthracnose problems on wintercreeper euonymus and those without anthracnose problems.

Shearing is an important cultural practice for maintaining plant size and appearance during nursery crop production. However, oakleaf hydrangea (Hydrangea quercifolia) is susceptible to dieback after shearing. The objective of this study was to determine whether foliar or substrate surface applications of ancymidol or uniconazole can reduce plant growth of oakleaf hydrangea similar to pinching, which was used to simulate shearing. ‘Alice’ or ‘Pee Wee’ oakleaf hydrangea plants were treated in 2002 or 2006, respectively, with ancymidol or uniconazole as a substrate surface application at 0, 1, 2, or 4 ppm; ancymidol as a foliar application at 0, 25, 50, or 100 ppm; or uniconazole as a foliar application at 0, 12.5, 25, or 50 ppm. Both cultivars received the same plant growth regulator treatments in 2012, and a pinched control was included in the 2012 experiment. Ancymidol and uniconazole had limited and inconsistent effects on growth of ‘Alice’ and ‘Pee Wee’ plants regardless of application method. Uniconazole was more effective at controlling growth of ‘Alice’ in 2002 when the study was conducted from October through December than in 2012 when the study was conducted during a more typical growing season of May through September. Plants treated with either ancymidol or uniconazole by either application method usually grew more during the first 2 weeks after application than those that were pinched. During the remainder of the growing season, little difference in growth between pinched plants and growth regulator-treated plants occurred. At harvest in 2012, pinched ‘Alice’ plants had more leaves but a smaller leaf area per leaf than plants treated with growth regulators resulting in no difference in total leaf area or in leaf, shoot, or root dry weight among the treatments. ‘Pee Wee’ treated with uniconazole using either application method or uniconazole as a foliar application had fewer leaves than pinched plants.

Four experiments were conducted under greenhouse conditions in Oklahoma. Pelleted ‘Genovese’ basil (Ocimum basilicum) seeds were sown in polystyrene flats with six different blends of a peat-lite mix (PL0) and yard waste compost [YWC (this batch designated C0)] in 2012 for the first two experiments. The proportions by volume of PL0:C0 included 100%:0%, 80%:20%, 60%:40%, 40%:60%, 20%:80%, and 0%:100%. Seedling establishment was unaffected consistently, but there was a distinct decline in seedling height and dry weight between 100% PL0 and 80% PL0:20% C0, followed by smaller decreases as the percentage of compost increased in the blends. A third experiment was conducted in 2013 with a different batch of peat-lite (PL1) after the compost had aged 17 months (now designated C1). Treatments were 100% PL1, 80% PL1:20% C1, and 80% PL1:20% C1 mixed with sulfur (S) at 1, 2, or 3 lb/yard³ of blend to acidify the media. The 100% PL1 treatment delayed seedling emergence and suppressed height and dry weight relative to seedlings grown in 80% PL1:20% C1 blends. The PL1 subsequently was found to have been produced in 2010, and the wetting agent had apparently degraded. The aged 2012 compost (C1) was not inhibitory to basil seedling growth when blended at 20% with the PL1, and in fact restored utility to the PL1. The carbon:nitrogen ratio of the original 2012 compost (C0) was 10.8:1, suggesting stability. It appeared that the main reason the C0 compost was inhibitory was that mineralization was slow or immobilization occurred, causing a lack of plant-available nitrogen, especially nitrate. Treatments with S lowered pH of the media, but there were no differences in basil seedling growth between the unamended 80% PL1:20% C1 blend and blends with added S. A fourth experiment compared three peat-lite media: PL1; a batch of the same medium as PL1 that was produced in 2013 (PL2); and a different medium also produced in 2013 (PL3). Peat-lite media were either used unblended, or blended with 20% C1 or 20% C2 (a fresh batch of YWC obtained from the same facility that had produced the original C0). The unamended PL1 was again inhibitory to basil seedling establishment and development. The two “fresh” peat-lite media (PL2 and PL3) were not inhibitory and were similar to each other in performance. A blend of 80% PL2 or 80% PL3 with 20% compost produced similar (C2) or somewhat better (C1) results than were obtained with the unamended peat. We conclude that a blend of 80% peat-lite medium and 20% YWC can be used to produce basil transplants. However, producers must consider the quality of the peat-lite medium and the compost based on the age and composition of the components.