The Ornamental Garden in May
This can be a very busy month subject to what you intend growing.
Providing all fears of late frosts has passed most bedding plants can be planted out this month.
As a rule of thumb, plant out the hardier annuals first, then follow these with the less hardy varieties.
Note: As with most advice on gardening the advisors location will often influence the content of the advice.
To alleviate this problem I have produced this chart indicating how you can make adjustments to the timing of events as seen in this website.
I hope you find this useful! .......Tg
At any time this month:
Inspect lilies for signs of Scarlet Lily beetles which are usually active at this time of the year.
Ensure that tall plants have adequate support.
Thin out congested Aquatic plants.
Week 18 - 30th Apr to 5th May.
If not done previously apply a top dressing of general fertiliser in readiness for planting out.
Be on the lookout for Lupin aphid.
Week 19 - 6th May to 12th May.
Plant out Penstemon if conditions allow.
Stop (remove tip) established Dianthus chinensis.
Week 20 - 13th May to 19th May.
Lift, replant or pot up self seeded Lunaria.
Pinch out the growing points of Actinidia arguta and chinensis when quite young.
Spray Roses to prevent major outbreaks of pests and diseases.
Deadhead Pieris after flowering.
Narcissus and ../Content/T/Tulips/Tulips.htm bulbs can be lifted and placed into store for planting elsewhere in autumn.
Week 21 - 20th May to 26th May.
If not done previously prepare beds for planting out.
Plant out Agastache, Agrostemma, Anomatheca, Arthropodium, Calendula, Callistephus, Carnations, Centaurea cyanus, Chrysanthemum annuals, Dianthus chinensis, Echium, Eschscholtzia, Gaillardia, Godetia, Gypsophila, Helichrysum, Iberis, Lavatera, Limnanthes, Limonium, Linaria, Lobelia, Lychnis, Mimulus, Nemophila, Nicotiana, Nigella, Nolana, Orache, Papaver / Poppy, Phlox drummondii, Portulaca, Reseda, Rudbeckia, Salpiglossis, Salvia, Schizanthus, Silene, Tropaeolum/Nasturtium and Verbena if conditions allow
Pinch out the tops of Salvia to encourage branching.
Watch out for signs of leaf spot and rhizome rot on Bearded Iris.
Week 22 - 27th May to 2nd Jun.
Plant out Ageratum, Alstroemeria, Alyssum, Amaranthus, Antirrhinums, Arctotsis, Bidens, Brachycome, Celosia, Cerinthe, Convolvulus, Cosmos, Dahlias, Gazania, Gerbera, Impatiens balsamina, Ipomea, Pacific Coast Iris, Laurentia, Lewisia, Marigolds, Mesembryanthemum, Nemesia, Nerium, Osteospermum, Pansy, Passiflora, Tagetes, Thunbergia, and Zinnia.
Keep Gladioli bed weed free.
Pot up Dahlias to grow as pot tubers.
Feed Aethiopica with a balanced liquid fertiliser at weekly intervals from now until August.