Bloom development starts in the bud phase of the plant. Buds are forming weeks before they enlarge and open into flower. In the period that the buds are forming, extreme weather can impact the outcome of the first few blooms. This can include extremes in heat, water or the shock of a heavy fertilizer application.
All plants have one mission to their existence, to grow, bloom and set seed to perpetuate themselves if you will. We have all appreciated the late fall and winter ‘seed heads’ on clematis, which add a unique beauty to the landscape in the colder months. Your clematis seed heads are actually the fruit of the plant.
In the early season it is best to deadhead spent flowers from your clematis plants. Here’s why. If you do not, the plant slows down bloom production as it is feeling like it’s mission is close to being accomplished. By deadheading early to mid summer blooms, you encourage the plant to keep blooming.
At mid summer, encourage your clematis plant further by trimming or pruning the plant. Fertilize and continue to enjoy more blooms. Late summer is good time to allow the plant to ‘set seed’ from the late flowers. This way you have the abundant bloom span, and still get to enjoy some of the unique fruit that will last for months on the plants as you enter the winter season.
Plant dormancy is stress as well as seasonally induced. Clematis plants have the capability to perform and look beautiful for a long season.
Hydration is important as the summer draws on and you may think leaving your garden to the rainfall takes care of all of the water the plant needs. Regular, deep watering will help your clematis plants achieve the full season the plant is capable of achieving.
After the main bloom period, pruning or at least deadheading and trimming back the plant, along with fertilizer and water will help the plant pause, then resume growing and support healthy, attractive foliage as well as subsequent blooms.
In hottest weather avoid applying fertilizer to the plant, and consider mixing the fertilizer at a weaker ratio in the summer. Watering before you apply fertilizer of any sort is a good practice also.
Be vigilant throughout the season about slugs also. Many insects do not bother clematis, another great reason to plant more clematis and take care of them throughout the growing season, but slugs can damage clematis throughout the season if not controlled.
Some varieties of clematis have a tendency to fewer stems than others, but in many cases this is created by our pruning habits. Every type 1 and 2 clematis benefits from being pruned hard at least 1, or even 2 times in the first year in your garden, semi permanent or permanent container. The time to do this is when growth seems to be stalled, or immediately after those long awaited first blooms. It is better to do this in the spring and early to mid summer. In the fall it is better to let the plant go into dormancy with the stem(s) left unpruned.
For clematis that continue to have one stem, even if they have been pruned as directed, it is important that as the first flush of blooms wane in the first few seasons to continue to re prune the plant. Remember to fertilize the plant after you prune.
For clematis that do not respond to your efforts, we suggest landscaping around the plant’s tendency.
Check our planting how tos and make sure that you are planting your new plants at the correct depth and angle to create health and more stems from the get go on new clematis additions.
One of the main causes of stem collapse is damage from wind or slugs. If you inspect the withering stem you can often see the damaged point, which sometimes is traceable to the point where you secured the stem to a trellis or structure without enough flexibility to allow it to handle the wind.
If you look at the stem on the lowest part of the plant you may see the outer ‘bark’ stripped away. This indicates that slugs may have damaged the stem to the extent it could no longer function to support growth and it will wither away.
For either of the above issues (on a larger clematis), starting at the top, remove the stem in pieces, working your way down and cutting and removing sections. When you get to the bottom, cut the stem at or just slightly below the soil level and discard the stem vs. compost it. Usually the plant will replace the stem immediately with a fresh shoot; sometimes it does take a few weeks for the growth to initiate. If the clematis is containered and there no other stems, or few stems, monitor and do not over water in this stage while there is little to no vegetative growth.
Fungal issues are rare, and as plants build resistance to your garden ecology, there should be few issues. Consulting an expert at your garden store is always an option. Often rose formulas for a variety of issues work well, but always test them on one clematis before using them on all of your plants.
In mid to late summer, browning lower leaves can be a sign of dehydration, so it is important to keep up watering through the entire growing season. When a plant does not need a leaf any more, the leaf does tend to be shed by the plant and the first part of that is a browning or yellowing off. Simply remove the discolored leaves with a pinch or a small pair of garden nippers.
Earlier in the season, yellowing or browning leaves that the plant is discarding can be from a variety of natural causes. These include temperature extremes that may have damaged the leaves in question, and water extremes such as heavy rainfall or periods of dryness.
Other leaf discolorations may indicate a problem with the plant’s uptake of nutrients from the soil, or very rarely , a bacterial or fungal condition.
Usually the plant works through minor issues naturally and all we can do as gardeners is make sure that water and nutrition are good, and remove unsightly leaves. In more serious issues, the entire stem or stems is affected. If the plant is growing well above the disfiguration, remove the leaves and watch it to monitor the over all health of the plant.
Do you have clematis that are bare on the bottom of the plant?
Bare bottoms are more likely on clematis that have not been hard pruned. In some cases this is because the gardener does chooses not to hard prune in the spring, or it can be a result of retaining the stems from the prior year on type 2 clematis.
There are two approaches to this.
- You can work with the bare bottom of your clematis plant by planting a taller shrub in front of the clematis, or a shorter perennial flowering plant that will provide some coverage of the base.
- In a mature plant with many stems, try hard pruning some stems to the ground vs. the first growth node. This encourages fresh new stems to emerge which will often have more lower foliage.