Q.
How can I increase moisture retention in the soil of my hanging baskets and patio pots? I used a commercial planting mix, which dries out rather quickly.
A.
Pot size is a first consideration. The larger the pot the easier it is to keep the soil adequately damp.
Most purchased potting mixes are lightweight and fast-draining. Adding a heavier, more substantial all-purpose sterilized soil adds substance and “staying power” to a mix. Another useful addition is coconut fibre (coir), which enhances moisture retention and acts as a buffer against temperature extremes.
For hanging baskets, which are not usually large, I sometimes use worn kitchen sponges, dried and saved, at basket bottoms to help hold moisture and release it into the soil as needed. I’ve heard of people using the absorbent, “working” section of (unused) diapers in the same way for moisture retention.
Q.
Are you familiar with something called the “Chelsea chop”? I heard the term used recently, but did not pick up any detailed information around it, except that it had something to do with managing the bloom time of some perennials.
A.
The Chelsea chop is a method for pruning some perennials to prolong flowering. It can be used on substantial clumps of tall garden phlox (Phlox paniculata), Monarda (bee balm), Heliopsis, Echinacea and similar plants.
In mid to late May (around the time of the famous Chelsea flower show), as flower buds begin to form, either the front half of the stems or the stems around the perimeter of the clump are cut down by one-third to one-half, making cuts above growing points at leaf junctures.
The pruning is followed by a mulching with compost, and regular watering. The cut stems will re-grow to bloom around six weeks later.
Steer clear of applying this technique consecutively for multiple years to any single plant to prevent it from becoming weakened.
