Oct. 7, 2010

Here's Randy's Weekly KTRH GardenLine Tip:

Issue #182

Have you noticed your iris or day lilies looking a little pale or beginning to outgrow their spaces? Are any of your other bulbs ... even perennials like calendulas ... dying out in the center?

If so, fall is the right time to divide and replant these and other spring- and summer-blooming plants that grow back year after year.

It's also appropriate because the 68th Annual Houston Bulb & Plant Mart is today, tomorrow and Saturday at the Westminster United Methodist Church, San Felipe at Bering. Plus, I'll be speaking there at 8:30 a.m. Friday.

Dividing established bulbs and perennials during autumn months is the easiest and quickest way to make them healthier. You'll also wind up with new plants for your garden or for sharing with neighbors.

The best candidates for division are perennials that have been in the ground several years and have large, healthy clumps. Here are the rules for dividing each category.

DIVIDING BULBS
Certain bulbs need to be divided or separated to maintain a healthy, flowering stand. Crowded bulbs are less likely to produce quantity and quality flowers. When flower numbers and size start to diminish, consider separating and replanting the bulbs. Bulbs planted at recommended depths initially require less dividing and resetting.

Spring-flowering bulbs like daffodils, tulips and hyacinths should be divided in September or October. Granted, it is difficult to determine the location of bulbs without staking or mapping them out previously. Care should be taken when digging to prevent damaging them. It usually is easier to dig up a large area and separate the bulbs then trying to dig up individuals.

If bulbs are planted among trees, shrubs or perennials, consider replacing them every three to five years instead of separating. This minimizes damage to the root system of the nearby plants. Summer-flowering bulbs can be divided in early April or late fall. Some, including surprise lilies (Lycoris) may not appear to need dividing. However, plants will produce more flowers if divided. When dividing or separating bulbs, you need to carefully remove side bulbs from the main bulb. Replant at correct spacing.

The following table provides a guideline for dividing bulbs.

Bulb	Years to Divide
Tulips	3 - 5
Daffodils	3 - 6
Hyacinths	2 - 3
Lilies	4 - 6
Surprise Lily (Lycoris)	3 - 5
Iris (Bulbous types)	3 - 6
Alliums	4 - 8
Crocus	seldom needed
Grape Hyacinths (Muscari)	seldom needed

DIVIDING PERENNIALS

1. Try to divide dormant perennials on a cloudy day when the weather is dry, making sure each plant division has more roots than shoots.
2. Use a shovel to dig deep all the way around the plant and gently lift out of ground with your hands.
3. Keep as much of the root system intact as possible. If working with a very large clump, force the shovel under the root ball to loosen before you lift plant.
4. Shake off loose soil and wash the crown with a garden hose until you can clearly see roots and crowns.
5. Each division should have two to five strong shoots with ample roots attached. Divide the plant into smaller clumps either by hand, or with a knife or spade. Roots of some older clumps can be so tough that you'll need to chop them with a hatchet.
6. Remove any dead areas and cut back remaining foliage to half the height of the original clump. Tall plants like Iris should be cut so the outer leaves are slightly shorter than the center leaves.
7. Replant divided perennials promptly so roots don't dry out. Set plants out at the same depth as before, making sure to replant one division back into the original hole.
8. Dig the hole slightly larger than the division to allow space for the new plant to spread out its roots.
9. To finish up, water thoroughly and apply mulch to keep soil from drying out and to protect the plant's root system.
10. Keep the soil moist until your new plant becomes established. Wait until spring before adding fertilizer.

BULB MART REMINDER The 68th Annual Garden Club of Houston Bulb & Plant Mart is Thurs.-Sat., Oct. 7-9, at the Westminster United Methodist Church, San Felipe at Bering. This is a must-go-to event for gardening enthusiasts, and especially for those interested in bulbs.

It's actually so much more than bulbs these days, but it's still what they specialize in. This year, I'm doing a talk at 8:30 a.m. Friday, so bring your wagon and your questions to this awesome event. By the way, even if you miss the talk because it's early, I will hang out at the Q&A table for a couple of hours after.
Saturday GardenLine Appearance 11 a.m. -1 p.m.
Plants for All Seasons, Highway 249 at Louetta I'll be visiting Plants for All Seasons immediately after Saturday's radio show. The event is again being sponsored by Lady Bug Natural Products, and I'll have a pallet of their goodies to give away. Just print a copy of this tip sheet and bring it to me for a chance to choose from the big bags of free product.

GardenLine Listeners and E-mail Tip subscribers:
Purchase a copy of my book,
Gulf Coast Gardening with Randy Lemmon,
at a discount!

CONTACT INFORMATION

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