Growing Perfect New Guinea Impatiens Baskets

The first step in growing the perfect New Guinea impatiens hanging basket is knowing how your customers define "perfect." For the independent retailer, the perfect plant might be 12" above the basket and6" to 8" out from the sides. This same basket might be unmanageable for the mass-market retailer and uneconomical for you to grow and ship at the prices they might expect to pay. In either case, plants should also be well-branched and flowering on top rather than down in the foliage. Most cultivars on the market offer these characteristics. The deciding factors in choosing cultivars are plant vigor and earliness. Choose more vigorous plants for the large basket sizes, and avoid the various "mini" lines even for compact 10"baskets. Vigorous cultivars can be used for the mass-market size plants if they flower early. Less vigorous cultivars can be used for the larger "premium" retail baskets if given longer crop time.

Next, inspect the rooted cuttings before transplanting. (It is not recommended that unrooted cuttings be stuck directly into hanging baskets.) Besides looking for disease and insect problems, check if the cuttings are budded. It’s best to use plants that are not budded in order to get a good plant size in the least amount of time. If the laterals are vegetative and the shoot tip is budded, then the liner cutting can be pinched to encourage vegetative growth for larger baskets. For compact baskets, you might not want to pinch.

Planting
Select a well-draining medium with the pH adjusted to 5.5 to 6.2. Most commercial peat mixes and bark mixes are acceptable. Water the baskets thoroughly at the time of transplanting, but allow the baskets to dry down between watering. Do not feed for the first two weeks. This will promote rooting to the bottom of the basket. However, do not dry the plants down to the point of hardening them off, as this will slow the initial growth severely. Do not drench the pots with fungicides unless you experience root rot problems.

Feeding
Once the plant roots are well established, feed with 100ppm nitrogen. Later, the rate should be increased to 150ppm to 200 ppm N. As with most plants, yellowing of the leaves could indicate too little feed. Watch for rippling or cupping of the leaves. This could be an indication of too much feed. Run soil and tissue analyses to confirm either of these conditions. Supply micro-nutrients either as a soil amendment or in the feed, but not both. New Guinea impatiens do not tolerate high levels of micro-nutrients.

Temperature
New Guinea impatiens should be grown between 68°F and 72°F, especially right after transplanting. Cooler temperatures slow the rooting process as well as the overall growth and flower initiation. Temperatures above 85°F inhibit flowering and reduce flower size. Light levels should be as high as possible, up to 6000 foot-candles. Under these optimal conditions, baskets should finish in 10 to 14 weeks.

As you can see, most of the attention in producing the perfect New Guinea impatiens basket happens in the first couple of weeks in order to get the plants properly established and growing. During the rest of the growing time watch out for disease and insect problems and treat them accordingly. Sales of New Guinea impatiens have been estimated to be increasing at the rate of 15% each year.Your care in producing quality products will help ensure that New Guinea impatiens remain a favorite of consumers.