600 bucket geraniums plus 50 buckets Sunpatiens
There are 2 main types of annual geraniums that we grow, trailing types and upright types. I will keep this brief and concentrate on the main problems in the care of upright geraniums (trailing geraniums care is here).
I read an article years ago (that I cannot find) stating geraniums were mainly found around bogs and as it rained uphill from the bog the runoff toward the bog/pond would water the roots. The plants adapted to grow with this regular watering as its way of surviving, just as other plants evolved to survive in desert conditions with very little rainfall. So we advise our customers to water geraniums daily in ground beds and patio pots. Doing so results in extremely large multiple flower heads. If customers tell me that their blossoms are never as large as when they purchased them from us, it is largely due to incorrect watering practices, letting the plants dry too far.. More frequent and thorough watering will result in large blossoms. Please irrigate your geraniums with a “open” hose around the base, no spray nozzles!!
When keeping the plants too dry yellow leaves develop from the bottom up making geraniums unsightly. The cause of the yellowing leaves is root loss due too incorrect watering. The lower leaves are the first ones affected by the lack of water. I must caution do not keep the patio pots in standing water, excess water must drain away or you will have different issues. Geraniums in ground beds would also prefer regular watering but standing water is less of an issue (be careful of clay soils).
When leaves are developing from the bottom of the plant upwards this tends to be from under watering (loss of roots-yellowing leaves). If plants are yellowing from the top down this tends to be be lack of fertilizing. While there can be a range of issues regarding the previous statement, my 46+ years of being a grower answers the main issues customers have with “What is happening to my geraniums?”