The end of May and early June is Iris season on Cape Cod so it’s not unusual to have a customer ask why these plants are flowering in their gardens. There are a few reasons that your Iris plants may not flower, and sometimes their lack of bloom can be a combination of two or more circumstances. Here are the main reasons Iris may not be flowering:
What month do irises flower?
A number of bearded varieties bloom from early spring to early summer. Among beardless irises, many varieties in the Spuria subgroup bloom from late spring to midsummer. Some Siberian iris (Iris sibirica) and Japanese iris (I. ensata) selections bloom from mid-spring to early summer.
How many times a year do irises bloom?
"Cycle rebloomers" produce a spring crop of flowers, then lie low during summer, and grow and flower again in the fall. "Repeaters" produce new flowers soon after the first spring flush dies back, extending the bloom season to one to two months. "All-season rebloomers" produce flowers irregularly throughout the season.
How do I get my iris to bloom again?
To get the irises to bloom again, you should apply the fertilizer a month after the first bloom. This is going to keep the plant healthy and will improve its quality too. Always use a fertilizer that is labeled to be used with bulbs.
Why are my iris not blooming this year?
When you notice iris plants not flowering, the cause can stem from a variety of issues including weather, soil fertility, overcrowding, unhealthy rhizomes, insect or disease attack, planting depth, and even site conditions.
Should you cut back irises after they bloom?
Iris plants are best cut back in the fall. Spent flower stalks can be removed in spring after the plants finish blooming, but the foliage should be left standing through summertime. In mid-autumn, cut the leaves back to about 3″ long above the soil line.
What do I do if my irises don't bloom?
It may be a good idea to divide and replant your irises. Find a sunny location receiving at least 6 hours of direct sunlight each day. Prepare the planting site by digging the soil deeply to loosen compacted soil. As you are turning the soil, add amendments such as compost and a phosphate fertilizer.
Will iris bloom first year?
To improve your chances of bloom, add fertilizer and divide large clumps. Only 60-75% of Iris bloom the first year after planting. Sometimes they need an extra year to become established. Unusual weather conditions or late spring frosts can also harm Iris blooms.
When can I transplant irises?
The best time to plant and transplant rhizomatous iris is late July through September. Iris loves the heat and drier weather of summer and the summer dividing will reduce the incidence of bacterial soft rot. Most rhizomatous iris should be divided every three to five years.
How do you keep irises from falling over?
He suggested staking the iris with small bamboo stakes for now and adding more soil. That should help the plant to establish itself. If there are a lot of irises in one spot, the problem could be that they need to be divided, Van Buren said. You should do this at the end of July or beginning of August.
How do you divide irises?
Carefully remove the entire clump with a spade or garden fork. Divide the rhizomes by pulling them apart with your hands. The rhizome should easily break off at a joint. If a sharp knife is needed to separate the rhizome, dip the knife into 10% bleach and water solution after each cut.
Do irises come back every year?
Irises grow from underground bulbs or fleshy roots called rhizomes and, with proper care, the National Gardening Association says they'll regrow season after season in zones 3 though 8, or even zone 10 in dry climates.
Will iris bloom more than once?
'Pink Attraction' reblooms at least once in a season up to and including USDA Zone 4. Reblooming irises, also called remontants, may not reliably rebloom every year, possibly due to vagaries in the weather, and sometimes due to lack of nourishment.
Do all irises multiply?
Irises multiply readily by growing new rhizomes that mature quickly. Because they multiply so quickly, irises are easy to share. Every few years, irises should be divided just like daylilies to rejuvenate the plant.
What do you do with iris seed pods?
Let the seedpods ripen and turn fully brown and begin to split open before you cut them off and store them in a cool, dry place. In the fall, as it begins to cool, plant the seeds in the garden in an area prepared with amended soil and that is weed free.
What is the best fertilizer for iris?
Irises should be fertilized in early spring about 6 to 8 weeks before bloom, and again after the blooms are gone. Because phosphate is important, we recommend bone meal or super-phosphate and a light balanced fertilizer such as 10-10-10 or 6-10-10 depending on the amount of nitrogen in your soil.
Can you transplant iris in winter?
October is a little late for transplanting iris but if the weather remains seasonably warm, you should be OK. Ideally, you should transplant them after blooming, from summer into fall.
Why are iris leaves turning yellow?
Yellowing iris leaves can be caused by overwatering, underwatering, root rot, incorrect soil pH, too much fertilizer, lack of fertilizer, wrong type of fertilizer, lighting issues, diseases, or pests. Identifying the problem and quickly correcting it typically results in fresh, healthy new growth.
What is the best soil for irises?
Iris will thrive in most well-drained garden soils. Planting on a slope or in raised beds helps ensure good drainage. If your soil is heavy, coarse sand or humus may be added to improve drainage. Gypsum is an excellent soil conditioner that can improve most clay soils.
Do irises like lime?
Perhaps you live in an alkaline pocket, too, but most of the south is acidic and irises need lime.
Should you mulch irises?
Since the rhizome likes to be exposed to the sun, we do not use mulch. Mulch can also create moist conditions around the rhizome and not let enough air circulation around the plant, which can cause rotting.