Fertilizer
| Name | Description | Frequency |
|---|---|---|
| Alam Potschke New England Aster | Plan to fertilize your asters in the spring when new growth appears. Use a water-soluble or granular fertilizer made for flowering plants. For the amount to use, follow the product label instructions. You also can enrich the soil with compost. | Spring |
| Annabelle Hydrangea | Fertilize Annabelle hydrangea annually at the end of winter with a slow-release, organic, acidic fertilizer with an NPK of 15-10-10 or 10-5-5. Alternatively, treat the leaves with kelp or fish emulsion foliar spray. | Spring |
| Astilbe | Astilbe plants need phosphorus to bloom, so choose a fertilizer with the makeup of 5-10-5 or 10-10-10. Rake the fertilizer into the soil two weeks before you plant, or sprinkle a few granules onto the soil after the astilbe has been planted. Once the plant is established, fertilize every spring when the soil is moist but the leaves are not. | Spring |
| Balmy Beebop Bee Balm | In its native habitat, spotted bee balm can grow in poor soil. That’s why in a landscape or garden setting, it might not need any fertilizer at all, or at the most a single light feeding with a balanced fertilizer in the spring. If in doubt, it is better to fertilize less or not at all than to over-fertilize, as excess nitrogen can negatively affect flowering. | Spring |
| Balloon Flower ‘Sentimental Blue’ | Balloon flowers typically don't need supplemental feeding if you have rich soil. But a layer of compost in the fall can help them replenish the energy they expend blooming during the growing season. If you have poor soil, use an all-purpose, slow-release fertilizer in early spring. | Spring |
| Balloon Flower ‘Astra White’ | Balloon flowers typically don't need supplemental feeding if you have rich soil. But a layer of compost in the fall can help them replenish the energy they expend blooming during the growing season. If you have poor soil, use an all-purpose, slow-release fertilizer in early spring. | Spring |
| Bearded Iris | In the spring, apply a low-nitrogen 6-10-10 fertilizer around your irises. Too much nitrogen will encourage foliage at the expense of blooms. Bone meal is also a good fertilizer. | |
| Black Adder Anise Hyssop | Feed your Anise Hyssop in early spring every other year with about a bucket of organic compost that has been sprinkled around the base of the plant. Make sure to target the roots and leave a couple of inches of soil space between the compost and the plant's main stem. | Spring |
| Black Tupelo | Feed this tree annually in the fall using a slow-release granular fertilizer. In general, use 2 cups of fertilizer per every inch of trunk diameter, measuring the trunk at about 4 feet off the ground. Sprinkle the fertilizer into the soil around the tree in an area that extends 1.5 times the distance from the trunk to the tips of the branches. | Fall |
| Bleeding Heart | Bleeding heart plants are not heavy feeders, so when to fertilize depends on the quality of your soil. If you have rich, organic soil amended every year, you likely won't have to feed at all. If you have poor soil, you can apply an all-purpose, slow-release fertilizer in the spring. Also, as a woodland plant, bleeding heart does well with a top dressing of leaf mold. | Spring |
| Bloody cranesbill | Give plants an extra boost by adding a granulated starter fertilizer or all-purpose feed that encourages blooming (for example fertilizers labeled 5-10-5). | Spring |
| Blue Blazes Hummingbird Mint | Agastache has no need of extra fertilizer but a top dressing of compost in autumn will keep it healthy. | Fall |
| Blue Fortune Anise Hyssop | Feed your Anise Hyssop in early spring every other year with about a bucket of organic compost that has been sprinkled around the base of the plant. Make sure to target the roots and leave a couple of inches of soil space between the compost and the plant's main stem. | Spring |
| Blue Mouse Ears Hosta | Proper feeding is one way to make hostas grow bigger. The best and easiest way to feed hostas is by adding a healthy layer of compost to the soil in the spring. This feeds nutrients into the soil and helps promote the soil food web. You can also feed hostas with a well-balanced organic fertilizer, applied after planting or when plants begin to come up in spring. But be careful not to get fertilizer granules trapped in the leaves, which can burn them. | Spring |
| Carpet Phlox | Fertilizing in the late winter or early spring will promote growth and support a more robust bloom for your creeping phlox. Feed it with a general slow-release fertilizer suitable for flowering plants, following label instructions. | Late winter |
| Coral Bells | Feed coral bells in the spring with a half-inch layer of compost or a light amount of slow-release fertilizer. This plant has light feeding needs; you should avoid heavy applications of quick-release fertilizers, as this will inhibit flowering. Container-grown coral bells benefit from feeding with a water-soluble fertilizer to replenish nutrients that leech from the soil. | Spring |
| Goldsturm Black Eyed Susan | Fertilize lightly in the fall with a half and half blend of Yum Yum Mix and good quality compost. | Fall |
| Cranberry Lace Bee Balm | Provide rich, fertile soil for the best growth of bee balm plants. Amend the soil yearly with compost or other organic materials to give this plant the nutrients it needs. Alternatively, a well-balanced fertilizer can also be used yearly in the spring. | Spring |
| Creeping Phlox | Fertilizing in the late winter or early spring will promote growth and support a more robust bloom for your creeping phlox. Feed it with a general slow-release fertilizer suitable for flowering plants, following label instructions. | Late winter |
| Cushion Spurge | Use cactus fertilizer if you want to provide your perennial with additional nutrients for good growth. | |
| Fireball Bee Balm | Provide rich, fertile soil for the best growth of bee balm plants. Amend the soil yearly with compost or other organic materials to give this plant the nutrients it needs. Alternatively, a well-balanced fertilizer can also be used yearly in the spring. | Spring |
| Garden View Scarlet Bee Balm | Provide rich, fertile soil for the best growth of bee balm plants. Amend the soil yearly with compost or other organic materials to give this plant the nutrients it needs. Alternatively, a well-balanced fertilizer can also be used yearly in the spring. | Spring |
| Great Blue Lobelia (aka Blue Cardinal Flower) | Since lobelia is a prolific bloomer and heavy feeder, you'll get the best results by fertilizing it every two weeks with a liquid fertilizer formulated for flowering plants. These typically are somewhat higher in phosphorus than in nitrogen and potassium, as phosphorus promotes more flowers. Mix the fertilizer with water in a watering can according to package directions, and apply to the base of the plant, avoiding its leaves. Continue to fertilize your lobelia regularly through the summer to keep it flowering. | Every 2 weeks |
| Hardy Hibiscus | Mom - “I fertilize in early spring with chick poop that I use on the rhubarb, just cuz it is in same garden.” Hardy hibiscus plants need plenty of nutrients and regular feeding. Feed your plant with a diluted liquid fertilizer once a week or a slow-release fertilizer three times a year, including early spring, after the first round of blooming, and mid-summer. | Every 2 weeks |
| Husker Red Penstemon | Fertilize sparingly. One time each year in the fall is enough. Apply a light application of an organic or natural fertilizer such as Yum Yum Mix as a top dressing around the plants. Don't use high nitrogen water soluble fertilizer like Miracle Gro | Fall |
| Hyacinth | The easiest way to feed new bulbs is to toss some bulb food into the hole at planting time. There are many fertilizers available for feeding bulbs—10-10-10 is recommended—or you can use an ordinary bone meal. Feed the bulbs a mere handful at planting and again in the spring when the new growth first appears by scratching some bulb food into the nearby soil and watering well. For the amount to use, follow the product label instructions. | Spring |
| Hydrangea | Typically hydrangeas thrive when fed an all-purpose, balanced fertilizer like a 10-10-10 N-P-K or 12-4-8 N-P-K. To increase the size and quantity of hydrangea blooms, consider a fertilizer with more phosphorus. Phosphorus is the middle number, so a fertilizer labeled 10-20-10 will do. If exploring slow-release granular fertilizer, choose one that is labeled "bloom boost," which may also have a higher level of phosphorus. In March, May, and July, lightly apply a fast-release fertilizer, spreading it around the drip line of the branches—not the base. Water well. When using a slow-release fertilizer, lightly cover it with soil to activate it. Sometimes fertilizer might not be necessary in the summer, since most hydrangeas bloom better when they are a little hungry for nutrients. If leaves begin to yellow and appear unhealthy, add a light dose of liquid iron twice a year or another fast-acting fertilizer to remedy the issue. Hydrangeas benefit from applying fertilizer in mid-to-late spring and additional intervals recommended by the manufacturer of the fertilizer you choose to use. While the first set of flowers start to fade, apply the same slow-release bloom-boosting fertilizer used in spring. Time-release fertilizers usually need to be reapplied every three months. Other types typically need to be applied every one or two weeks. Then, in late winter, just before hydrangeas come back from dormancy, feed them another dose of an all-purpose fertilizer. | March, May, and July |
| Karen Azalea | Azaleas also do well if given some fertilizer. Without knowing the nutrients in your soil, a basic 15-15-15 fertilizer containing equal parts nitrogen, phosphorous, and potassium is your best bet. But there are special products made just for azaleas: Espoma's "Azalea-Tone" is a good one. Acidifying fertilizers are a good choice where soils are in the neutral or alkaline range. Fertilize in late winter or early spring, no later than the last week of March. | Spring |
| Little Lanterns Dwarf Columbine | Use a liquid, water-soluble fertilizer once a month during the growing season (spring to fall) to promote healthy foliage and better blooming. This plant requires phosphorus for healthy root development. Fertilizer too high in nitrogen can affect flower production; try using 5-10-5 NPK fertilizer, which is boosted in phosphorus. | Every 4 weeks |
| Love-in-a-Mist | Add a general-purpose fertilizer to the soil when planting Nigella damascena, and then fertilize it once a month afterward. For the amount to use, follow the product label instructions. | Every 4 weeks |
| Penstemon 'Blackbeard' | Feed beardtongue plants once a year with organic fertilizer, applied in the fall. Feeding these flowers with conventional bloom-boosting formulas can promote too much growth and can shorten the life of the plants. | Fall |
| Rose of Sharon | Fertilizer is recommended, though it's not mandatory for established shrubs unless you have poor soil. Use a slow-release fertilizer for shrubs and trees in the late winter or early spring, following label instructions. If you wish to grow organically, work compost into the soil around the root zone of the shrub in the spring. | Spring |
| Rudbeckia Maxima “Dumbo Ears” | You can fertilize your plant by using a water soluble feed. Feed your great coneflower once every two weeks in the summer blooming season (June). | Every 2 weeks |
| Siberian Iris | Siberian iris performs best if fertilized with a balanced 10-10-10 fertilizer in early spring, then again after flowering is complete. For the amount to use, follow the product label instructions. If you wish, an application of compost can serve as the early spring feeding. Where soils are too alkaline, a yearly feeding with an acidifying fertilizer may be helpful. | Spring and after flowers |
| Tiger Lily | Tiger lilies don't need much fertilizer. A layer of compost around the base of the plants once or twice a year should provide all of the nutrition they require. Apply mulch in late spring to keep the roots cool during the summer. If you want to encourage more flowering, you can use a 5-10-5 fertilizer. When growing these plants in alkaline soils, feeding with an acidifying fertilizer might be beneficial. | Spring |
| Yellow Daylily | Most daylilies do not need fertilizer. Instead, add compost each season to provide added nutrients to the plants and amend the soil. | Spring |