Perennials should be planted in an area of the garden or landscape that has good air circulation. This will help to avoid or cut down on disease problems.
With a little pre-planning and moderate attention, perennials will live 3 to 5 years and some even beyond.
They like soil rich in organic matter with excellent drainage.
Loosen up the soil with a spade, hoe, or fork. Mix in organic matter such as aged manure, aged compost, leaf mold, or pine bark humus. If the area does not drain very well, mix in some coarse sand or create raised beds.
Most perennials enjoy a pH of around 5.5 to 6.5 (depending on the normal soil level in the area). Soil testing is recommended, as fertilizer is a soil-balancing agent.
Without a soil test, use a neutral fertilize such as 10-10-10 in timed-release granular form. Follow the directions on the label for use.
Plant the perennials in holes that are several inches wider and deeper than the container and so that the top of the potted area is 1 to 2 inches above the ground level.
Fill in the hole with additional soil and water well to remove the air pockets. Then apply more soil to top off. Water every day to couple of days for the few weeks unless there adequate daily rainfall to soak into the soil where the root system is located. After 2 to 3 weeks, gradually taper off the watering to every few days for the following 3 to 4 weeks depending on local weather.
Rule of thumb on watering: Allow the soil to dry out for about a day before watering sessions. The slight dryness will allow the roots to stretch to look for moisture forcing root growth. Check the soil daily for the first 3 weeks especially when planting in late spring to summer.
Avoid getting water on the leaves or flowers. Mulch the perennials with a 1 to 2 inch layer of compost, straw or other natural mulch. This will help cut down on weed problems and keep the ground cool and moist.
Weeding is best handled by the hand method of pulling the weeds up at least during the first year in the ground. Some newly planted perennials may not bloom during their first year. Taller growing perennials may need support by staking with bamboo or other wooden or metal stakes and string.
Deadheading flowers encourages new blooms and new growth. After their blooming period, if a perennial looks somewhat withered, cut it back by about half allowing it to produce new growth.
In fall/winter, remove all dead foliage and stems, then mulch for seasonal protection.