Hydrangea Grow Guide

Hydrangea plants are easy shrubs to maintain and they reward the gardener with huge, eye catching flowerheads that can last for weeks. Not only that, after they bloom, the flower heads are beautiful and long lasting in dried arrangements.

Perfect Plants offers three different types of hydrangeas for different uses in the home landscape. Place an order online today to buy hydrangeas and have them shipped to your home. Use this planting guide to aid you in growing the hydrangea varieties you know your landscape needs.


Hydrangea macrophylla ‘Penny Mac’ 

penny mac hydrangea

Penny Mac exhibiting both pink and blue blooms and sometimes purple depending on soil pH

The classic big leaf hydrangeas produce spherical flower clusters that are blue when grown in acid soil and pink in alkaline soil. For blue flowers, the soil pH should be lower than 5.5. You can use aluminum sulfate to lower the pH. For pink flowers, it should be 6.5 or higher. A soil pH between 5.5 and 6.5 will lead to purple flowers or a combination of blue and pink blooms on the same plant.

‘Penny Mac’ is great in shrub borders, behind shorter flowers in beds, and is especially eye-catching in a specimen grouping of hydrangeas. This pink or blue evergreen shrub is perfect for your landscape. Prefers morning sun and afternoon shade for best results. Blue hydrangeas are a beautiful sight for all. For mophead hydrangea color help/pH of soil contact us!

Hydrangea paniculata ‘Limelight’ 

limelight hydrangea flowers

Limelight blooms late summer

This hydrangea has huge cone shaped flowers. It gets up to 8 feet tall, and is more drought tolerant than the others. Soil pH does not affect the white flower color. Most adaptable hydrangea to soil types. The panicle hydrangeas are well suited for the corners of a landscape or in mixed shrub borders. With thoughtful pruning ‘Limelight’ can be an attractive shrub, or trained to be a small tree. The hydrangea flowers on this genus appear off white/yellow lime colored – which is where it got it’s name.

Limelight Hydrangea Tree visual appeal

Limelight Hydrangea Tree

Hydrangea quercifolia ‘Oakleaf’

Oakleaf Hydrangea

Oakleafs grow on woody stems, be sure to not prune in spring

This hydrangea is an American native that pretty much takes care of itself. It is extremely low maintenance! It can get over 10 feet tall, is rather rangy in appearance, and is best suited for a woodsy or naturalistic garden. Flower color is not affected by soil pH.

 

Where to Plant Hydrangeas

How much sun do hydrangeas need? Most evergreen hydrangeas do best with full sun for 2-4 hours of sun in the morning, and partial shade or partial sun in the afternoons. Avoid planting locations with full-on sun all day, unless you are in zones 4 or 5, where full sun is recommended. The further south you are, the more your hydrangeas need afternoon shade. Oakleaf hydrangea tolerates more shade than the others, and Limelight hydrangea likes a bit more afternoon sun.

Choose a site where soil drainage is good, but not extremely dry. A rich, fertile, sandy loam is best; avoid distinctly sandy locations where roots can dry out quickly, and avoid garden soils or potting mix that stays wet where roots can rot.

Hydrangeas prefer well draining soils that are moist soil but no wet feet. Oakleaf hydrangea thrives in limey soils with a pH level around 7.0 or above. The other hydrangea shrubs like an acidic soil, and do best with pH values between 4.0 and 6.5. Peat moss will help lower pH.

Planting more than one bush and need to know how far apart to plant hydranges? Position them at least 3-6 feet apart. Try to plant new shrubs in spring/early summer or fall, rather than the dead of winter or the heat of late summer.

How to Plant Hydrangeas

Before beginning, thoroughly water the shrub in its original container. Place the pot on its side and slide the root ball out. If the plant is stuck, you can slip a long-bladed knife around the inside edge to loosen it. Gently loosen some of the roots along the sides and bottom of the root mass, and pull them outward so they are not encircling the root mass.

It shouldn’t be necessary to prune any of the roots unless they are wound around the circumference of the pot. In that case the offending roots should be shortened so that when they are in the ground they will grow outward and not continue growing in a circle.

plant a hydrangea

Dig a hole twice as wide as the container the hydrangea came in and about the same depth. Mound up some garden soil on the bottom in the middle of the hole and place the center of the hydrangea’s root mass on top of the mound, spreading the roots out all around the center. Backfill the hole about half way, then water thoroughly. After the water drains, continue backfilling until the top of the root crown is at the same level it was in the original pot, never lower. You may have to pull the plant up a bit as you backfill. Gently tamp the soil down.

Build a 3-6 inch high levee of soil on the surface around the outside of the root zone. This will impound water and allow it to sink into the soil directly over the roots. Water thoroughly. Spread an organic material or mulch 3-6 inches deep over the root zone and beyond to help hold in soil moisture. You can use hay, straw, leaves, pine needles, bark or wood chips, grass clippings or compost. Do not fertilize at this time.

Hydrangea Plant Care

Keep your hydrangea well watered during its first growing season is the best care for hydrangeas. If planted in the fall or winter, you can water once every week or two. If planted during the growing season, it should get watered every day or two for three or four months. If you’re having a dry spell, or your soil is very sandy, you should water every day for the first three or four months. The most common reason for any newly planted shrub to die is lack of enough water.

Hydrangea watering is most important the first of planting to let those extensive root systems grow. Soaker hoses work wonders or you can also use a tree gator. Re-fill the tree gator several times a week depending on the water requirements for your plant. Once established (after a year of growth), hydrangeas can tolerate moderate dry spells and should not need any supplemental watering unless it hasn’t rained in four weeks or more.

Feed hydrangeas once a year in late winter or early spring with a balanced fertilizer, or one high in phosphorus, which promotes flowering. Too much nitrogen fertilizer encourages leafy growth at the expense of blooms. A slow release fertilizer at the base of the plant will encourage growth and repeat blooms each year.

Pruning Hydrangeas

Hydrangeas generally do not need any pruning. Prune them only if necessary to maintain size or a desired shape or to remove dead branches. If you are wondering how big hydrangeas get if depends on the variety of hydrangea you choose. Hydrangeas will grow to the planting site you plant them in

The bigleaf hydrangeas (such as ‘Penny Mac’) and the panicle hydrangeas (including ‘Limelight’) form their flower buds on new wood, so any pruning should be done in winter or early spring before the new growth begins. Spring or summer is the wrong time of year to prune.

Oakleaf hydrangea blooms on old wood, so if you prune in winter or spring you will be cutting off the current season’s flower buds. Instead, the best time of the year to prune oakleaf hydrangea (although it’s almost never called for) is soon after flowering, before next year’s buds form.

To rejuvenate a senescent or leggy hydrangea, cut it back almost to the ground. You may not get any flowers the first season after that, but you will be amply rewarded in subsequent years. Growing hydrangeas is easy once you get the hang of it!


Once established, hydrangeas are very low maintenance shrubs that will be enjoyed year after year.

hydrangea landscape flowers