American Plant Blog

June Gardening Tips

Houseplants and Outdoor Tropicals
Houseplants placed outside for the summer will require diligent watering. If you will be away from home on vacation you can partially burry the pots in the ground to help them stay moist. Air conditioning tends to dry the air inside the home – mist plants daily or place on humidity trays. Continue to fertilize your houseplants following label instructions. Continue to fertilize outdoor tropicals with a combination of Osmocote and Superbloom. Remember to leave them in their original nursery pot for best flowering.

Vegetables and Small Fruits
Make successive plantings of green beans and beets every two weeks through august. This will give you more manageable yields and extend the harvest. Use straw as a mulch around your strawberries and place some underneath your melons and squash as they mature to prevent rot. Do not allow vegetable plants to become over mature – promptly harvest when they are young and tender this will extend your harvest.
Harvest vegetables and herbs in the morning- this ensures best flavor and texture. Harvest broccoli before it starts to flower. Cut out the central cluster and leave the side clusters for future harvest. Continue cutting asparagus through mid month - after this allow the foliage to mature for the rest of the season. Protect small fruits with bird netting just as they begin to ripen to deter birds and squirrels. Pick strawberries when they are completely red, leave the cap on for best keeping. Pick blackberries every 2 or three days for a better yield. Continue to monitor for pests and disease and use organic controls.

Fruit Trees
Harvest early ripening stone fruits. Continue an organic spay program on fruit trees until harvest. Remove any dead branches that did not leaf out. Mark any branches that suffered fire blight so they can be pruned out in winter to prevent problems next year.

Lawn Care
Complete laying sod early in the month – it is difficult to establish turf in the hottest months of the year. Begin watering your lawn if we are not receiving sufficient rain. Lawns will remain green in summer if they receive 1 inch of rain per week. You can measure this with a rain gauge. You will want to water deeply and infrequently approximately once a week if we get no rain. An oscillating sprinkler left running for 1 hour will provide about 1 inch of rain. It is best to water in the morning. Do not fertilize your lawn in summer – compost tea is a great tonic for lawns this time of year.

Continue to plant annuals use Espoma Bio-tone if planted in the ground. Continue to fertilize potted plants and hanging baskets with Superbloom weekly. Containerized plants will need more water as they grow larger often daily or twice daily. Place hanging baskets on the ground in the shade if you will be away on vacation. Use water a holding gel like DriWater in your containers this product is safe for edibles.

Continue to plant perennials. Use Espoma Bio-tone for best results. Dead head spent flowers to extend blooming. Continue to stake tall plants and pull weeds. Lightly cut back candytuft, moss phlox, and arabis now to keep them vigorous they can also be divided at this time. Continue to monitor for pests and disease.

Trees and Shrubs
Continue to plant containerized trees and shrubs. Balled and burlapped plants can still be planted if they were dug earlier in the season or if they have been treated to allow summer digging. Use Espoma Bio-tone for best results. Water any newly planted tree or shrub every 7 to 10 days deeply and thoroughly. Larger trees require approximately 25 gallons of water per week for best establishment this time of year. Plants on slopes or in fast draining soils may require more frequent watering. Continue to monitor for pests and disease.
Deadhead rhododendrons, azaleas, mountain laurel, tree peonies and Japanese pieris to keep them compact and healthy. They will also flower much better next spring. Continue to monitor for lacebug. You can continue to prune needled evergreens this month. Spruce and pines can be kept more compact by candle pruning always leave 1 inch of the candle intact when you remove the tip.

Prune climbing roses now by removing all 3 year old canes at ground level. They can be lightly pruned again in fall if needed. Continue to apply Espoma Rose-tone and water on a regular schedule for best flowering. Roses enjoy 1 inch of rain each week. Use a rain gauge to determine the amount of rain you are receiving. On individual plants that is approximately 2 gallons per week. Roses will flower best in cooler temperatures - in summer the flowers will be smaller as well.

Water Gardening
Keep your pond free of algae naturally by using a combination of Barley Straw Pellets and Microbe-Lift. Thin out water hyacinths if they are completely covering the surface. Fertilize with an aquatic fertilizer. Continue to plant tropical aquatics this month.

May Gardening Tips

Houseplants and Outdoor Tropicals:
When placing foliage plants outdoors for summer - slowly acclimatize them to their new position outside. Keep them shaded from the strongest sun of the day until the foliage hardens off. Indoor plants may need to be relocated if summer sun coming through the windows as well. Begin feeding outdoor tropicals like hibiscus with a combination of Osmocote indoor outdoor formula and water soluble fertilizers. This will ensure that they will look their best all season. Gardenias will appreciate a water soluble fertilizer for acid loving plants and Osmocote. It is also beneficial to leave them in the container they were grown in; this will help them bloom more often. These nursery containers can be planted into larger pots as well. Remember to water often in hot weather.

Lawn Care:
It is now too late to seed; use sod to fill bare spots or to cover larger areas. Sod will require careful watering in warm weather generally twice a day. It is also too late to control crabgrass with pre emergents like corn gluten. Zoysiagrass plugs are available by mid month. Zoysiagrass is mowed shorter at 1 to 2 inches. Continue to cut your (fescue) lawn at 3 inches this will keep your turf healthy and prevent weeds.

Edibles Vegetables:
Plant heat loving vegetable transplants like tomatoes, eggplant, okra and peppers around mid month when the soil has warmed. It is best to put in your stakes and cages for tomatoes at the time of planting. Plant basil seeds now at 2 week intervals for a summer long harvest. It is also time to direct seed beans, squash corn, cucumbers and melons these are best sown in mounds of soil. Soak the seeds overnight for best results. You will need a large area for success with corn typically 10 feet by 10 feet for best pollination and full ears. Remember to fertilize with Espoma Plant-tone following label directions. Monitor for insects and apply an organic control if needed.

Fruit Trees and Small Shrubs:
Continue to spray fruit trees with Neem oil or an organic formulated fruit tree spray. Thin heavy fruits sets if you have not already done so. Monitor small fruits and apply an organic insect or disease control if desired.

Continue planting perennials. You can divide early blooming perennials now after blooming. Pinch back summer and fall blooming perennials for more blossoms and to reduce their size. Use Espoma Bio-tone for best results. Tall growing plants will need staking - do this before plants fall over. Monitor for insect pests like flea beetles throughout the season. Apply Sluggo to safely control slugs and snails.

At mid month plant cannas, bananas, elephant ears and dahlias, do not water dahlias much until the foliage appears to prevent rot. Use Espoma Bio-tone if planting in the ground. When selecting hanging baskets carefully consider the location they will be placed in. Hanging baskets are more sensitive the extremes of heat and drought than plants in the ground. Begin feeding with Super Bloom and continue feeding weekly throughout the season. Hanging baskets in full sun will require careful watering for best results – use water holding gels like DriWater (this product can be used on edibles). If you are traveling place them on the ground in a shady area while you are away.

Tree and Shrubs:
Continue planting containerized and balled and burlapped trees and shrubs. Use Espoma Bio-tone for best results. You may prune cherries and magnolias lightly now - they are sensitive to hard pruning. Prune climbing roses this now after the first flush of bloom. Monitor for pest and diseases.

Water Gardening:
Plant tropical aquatics towards the end of the month when the water temperature is 70 degrees.


Houseplants and Tropicals:

It is time to bring your tender houseplants inside. Make sure to treat them for insects and spider mites before bringing inside. Espoma Earth-tone Insect Control is very effective. Spray the upper and lower leaf surface and small twigs twice 10 days apart you may make your second application inside.

Summer tropical bulbs and tubers like cannas, bananas and dahlias can cut back and moved inside after the first frost. Wash them well and allow them to dry for several days before you pack them up for winter storage.

Fall and winter blooming orchids should be producing flower spikes now. Use a bamboo stake and clips or twine to train the spike to grow straight.

Lawn Care:

Continue with fall lawn renovation, over-seeding, and fertilizing. You should complete these tasks by the third week of October. This allows the seed to germinate and root before the leaves fall.

Apply lime and Milky Spore now.


After harvest the vegetable garden should be cleaned up and the soil turned or tilled. If you are creating a new vegetable bed fall is a great time. The soil you turn over will be much easier to work next spring due to freeze thaw cycles. This also has a more positive impact on soil beneficial fungi and bacteria.

Remember to rotate your crops next year to minimize pest problems you may have had this summer. 

Annuals and Perennials:

Plant pansies now and enjoy them through next spring. Treat them with repellants if deer and rabbits are a concern and remember to fertilize.

Ornamental cabbage and kale can be planted later this month as well.

It’s time to plant most bulbs delay tulip planting until November. Use oyster shells or Espoma Soil- Perfector added to the planting hole to keep rodents away.

Cut back perennials as the foliage withers. Ornamental grasses can be cut back later in winter.

Trees and Shrubs:

If deer are a concern in your area now is the time to protect young trees from rutting bucks. Bucks mark their territory by rubbing their scent glands on trees and in doing so their antlers severely damage the trunks and can ruin trees. Use three hardwood stakes placed close to the trunk as a barricade. The stakes can be removed in January.

Many evergreen plants loose a portion of their older leaves or needles this time of year so don’t be alarmed. Azaleas, Japanese hollies, rhododendrons, false cypress, pines and euonymus are the most noticeable. Just late nature take its course.

It is time to fertilize your trees and shrubs with an organic fertilizer. This will stimulate root growth and give the plant better winter hardiness.

Continue to water regularly if its dry until the trees looses their leaves.

Delay fall mulching of beds until we have had a few nights of freezing temperatures. Mulching earlier keeps the soil too warm and plants may not harden off well.

Delay significant pruning of trees and shrubs until late winter.


Bulbs have always been popular garden plants. They are the harbingers of spring, are easy to plant and uniquely rewarding. But they are not just for spring -- there are summer bulbs like gladiolas and dahlias, fall crocus, and indeed bulbs like amaryllis and forced spring bulbs that are very popular for winter cheer.

I will not focus on tulips and daffodils, though they are great plants in both color and form and are deservedly popular. What I would like to share with you today are some observations I have made over the years on some underutilized bulbs and how to combine them with other plants for successful gardening.

Minor bulbs and friends:

Minor bulbs are called minor because they are not well known, and as a result less common. This does not mean they are difficult of culture or are less rewarding, they are just not a popular as daffodils or tulips.

Eranthis hyemalis, or winter aconite, is a late winter bloomer often poking its yellow flowers through melting snow on sunny days in January or February some years. They perform well under trees as they can complete their growth early before the trees leaf out. It is often combined with Galanthus, the snowdrops, which bloom with them. This combination looks smashing under witch hazels and truly warms the heart on winter forays in the garden.

Galanthis, or snowdrops, are more widely grown and with good reason. They bloom early under the tree canopy and are show stoppers. Invite your friends over for a snowdrop party when they are at peak. They grow equally well in a sunny exposure and will increase on their own, forming large colonies that bloom for a month each winter. Galanthis nivalis is very showy and the easiest to grow.

Anemone blanda is another rewarding minor bulb. Blooming in blue, white or pink these plants have attractive foliage as well. They prefer good drainage and a hummus rich soil. Try planting amongst ferns as the fronds unfurl. They will complement and then cover the foliage, which goes dormant in late spring. They perform well in bright shade to sun. They also look great as potted plants to be placed in the garden after blooming. Try combining with Ipheion uniflorum, candytuft or violas.

Scillia sibernica, or Siberian squill, is a favorite of mine. It is great for naturalizing and looks best planted in large drifts and is easy to grow. The nodding blue flowers look great under spring flowering magnolias. It also works well with Aurinia saxatalis on a sunny slope. Scillia will tolerate a lot of sun if not allowed to dry out completely.

Iris reticulata is an early blooming diminutive gem that combines well with spring Crocus. ‘Purple Gem’ is a really nice variety.

Crocus tommasianus is gorgeous and is not eaten by squirrels!

Here is a recipe for a low maintenance long season combination for you to try. You will need about a half a day of sun.
Compose a bed of Eranthis, Galanthis, Iris reticulata and Crocus with the long blooming perennial Ceratostigma plumbaganoides or Plumbago. The bulbs will give you an extended show in winter and spring. The Plumbago will grow on to cover the spent foliage and delight you with blue flowers in summer and red fall color.

Three for early fall planting:

Cycalmen coum is really a neat plant in flower and foliage and will not disappoint. It also thrives in the shade of large trees and will spread nicely, by seed, if happy. Interestingly, ants spread the seed. Though one can plant it from dormant corms available in fall, you may have better luck if purchased as potted plants. In addition to lovely flowers, the foliage has silver overlays. It will bloom in late fall through early winter. These treasures go summer dormant and like to be dry that time of year. Try facing down a yew hedge or combining with rhododendrons. Colchicum, or fall Crocus, is a winner and is resistant to deer and rabbit feeding. It does best in sun. One often sees photos of colchicums blooming in turf grass in European gardens. This is rather difficult here, with our vigorous overfed tall fescue lawns. You will need to delay spring mowing to let the foliage mature. Try it in the thinner grass of shaded areas or around the base of trees.

Spring Crocus should also be planted earlier than other bulbs in early September.   The problem with spring crocus is that rodents find them delectable. Simply planting them incased in wire mesh solves the problem and makes them less prone to being disturbed when planting near them in the future. Crocus t., as mentioned, above is not eaten. Crocus come in a variety of colors and sizes and will spread if welcome. All crocuses perform beast in well-drained soils. They are also great for forcing and will last longer if kept cool indoors.

Alliums and Dahlias:

Most great pairings are random. Alliums combined with ball dahlias just works. The form of the round flowers repeated from spring until frost adds continuity and color without much bother. Alliums are a love of mine and I have grown all of the worthy ones and will always consider them great perennials. The flowers have such amazing texture and color, floating on thin stems and most dry extremely well. They are also commonly available as potted plants, as well as, bulbs.

Dahlias are also a love of mine. They are easy to grow and flower prolifically till frost. Dahlias come in a variety of flower shapes but I like the ball dahlias and once grew every worthy one, just like the alliums, and randomly they  made the best border I ever made.

Alliums require only sun and good drainage like dahlias and are not bothered by much other that wet soils. Alliums are garden plants and dahlias are tender bulbs (tubers). So dahlias must be lifted and stored in a cool dry place after frost has blackened the foliage. Not a hard thing to do at all -- some cedar shavings and cardboard boxes are all you need. Check monthly and don’t keep too them wet or dry. If they rot just buy new ones.

Roger Zinn

...Hello September

leaf web

September Gardening Tips

Houseplants and outdoor tropicals:

When night temperatures reach 55 and below its time to bring tender plants indoors. 

Make sure to bring plants in clean and insect free. 

Examine plants for spider mites, scale and mealy bugs. Spray them twice 10 days apart with neem oil before you bring them in.

Discard plants that have lost vigor, they will not do any better indoors.

Expect to see some leaf drop as these plants adjust to indoor conditions. 

Water less frequently and feed sparingly until the plants have acclimatized.

White or tan crust on the top of the soil indicates salt build up from fertilizer. 

Repot plants into fresh potting soil and remember to flush out the containers with water every few weeks.

Lawn Care:

Fertilize your lawn now with an organic lawn fertilizer.

It is also time to aerate or dethatch, seed and lime. 

Ask our lawn care experts about the best practices and products.

Fall is the best time to apply lime although you may do it in spring and summer as well.

Milky Spore for grub control is also best applied in fall.


You may continue to plant spinach and radish seeds for fall harvests. 

Plant vegetable starts of cool season vegetables now.

Plant garlic now for harvest next summer.

Harvest carrots now before they get woody.

Harvest onions when the tops fall over.  Allow them to cure for a few days. Store them in baskets or mesh bags.

Figs are ripe when they change color and begin to droop on the stem.

Annuals and Perennials:

Plant crocus, cyclamen and colchicum bulbs now.

Daffodils can be planted at the end of the month if we have had normal temperatures. 

Plant tulips and Dutch iris in November.

Divide and transplant lily of the valley now, replanting them just below the surface about 3 inches apart.

Remove spent summer annuals and replace with pansies, cabbage and kale.

Pansies planted now will still be blooming next spring!

Trees and shrubs:

Do not fertilize trees and shrubs now-wait until late October.

Do not prune trees and shrubs until late winter or early spring.

Water trees and shrubs once a week if we get no rain. 

Keeping plants hydrated this time of year greatly improves hardiness and vigor.

Now is a great time to plant a new tree or shrub with our long growing season. There is still plenty of time for establishment before winter.


Summer Gardening Tips


Keep your indoor plants away from air-conditioning ducts or window units. The constant cold drafts are hard on plants especially Scheffleras.

Do not overwater plants kept inside.

Use a natural water holding gel such as DRiWater if you will be away from home.

Continue to fertilize houseplants following label instructions.

Outdoor Tropical plants and Annuals in containers:

Continue to feed with a combination of water-soluble and time-release fertilizers.

If you will be out of town relocate containers to a shady area and group together to conserve moisture. Drip irrigation systems work nicely as well.

Use natural water holding gel products such as DRiwater to help them through the extreme heat.

Lawn Care:

Do not mow grass if the temperatures are above 90 degrees.

Apply compost tea to help with heat and moisture stress.

Continue to mow at 3 inches this will suppress weeds and keep lawns greener.

Remove stubborn weeds by hand and replace with sod. Apply Weed-Be-Gone following label directions as a selective herbicide.

Lawns require 1” of rain per week to stay green. Please water accordingly.

Have us check your pH now for fall liming and fertilizing in September.


Maintain even moisture in the vegetable garden. Ripening tomatoes do not like swings in moisture and will split. This will increase your harvest of other veggies as well.

Continue to apply organic fertilizer such as Plant-Tone for better crops and vigor.

Apply Serenade for powdery mildew control on cucumbers squash and melons.

Remove old fruiting canes from June bearing raspberries at ground level.

Cut back new canes of blackberries and raspberries to 3 feet.

Place straw or newspaper as mulch under your melons and pumpkins to reduce decay.

Protect ripening grape bunches with paper bags until harvest.

Remove flowers from annual herbs like basil for a better yield.

Fertilize figs towards the end of the month.

Annuals and Perennials:

Continue to dead head spent flowers for continued blooming.

Stop pinching Mums by mid-month.

Continue to feed bedding annuals monthly.

Cut summer annuals, perennials and herbs for drying late in the month. Strip off the leaves and hang bunches upside down, a screened porch or garage work well for this.

Trees and Shrubs:

Remove suckers from trees especially from below the graft if present. This will keep you trees vigorous and healthy.

Control powdery mildew on trees and shrubs through out summer with Serenade.

Head back wild and irregular growth on holly trees, but do not remove the leader.

Prune now for height reduction on overgrown shrubs.

Continue to provide deep watering at 7 to 10 day intervals on new trees and shrubs.

Continue to fertilize roses monthly with Rose-Tone and water weekly.


Citrus time again!

Citrus never really goes out of style, George Washington had an orangery at Mount Vernon and had been popular for thousands of years before his time.  They have a lot to recommend them; fragrant flowers, colorful and delicious fruit, attractive evergreen foliage and are packed with vitamin C and other nutrients.  Citrus makes a great container subject in our climate going outside in May and inside when temperatures dip into the 40’s in October.  I have had a ‘Meyer Improved’ lemon for 17 years and it still looks good and produces plenty of fruit.

Citrus is easy enough to take care of requiring only good sun, careful watering, and proper fertilizing.  The most important thing to keep in mind is not to overwater!  One major reason plants get too much moisture is over-potting i.e. using too large of a pot! Soggy conditions several inches below can go undetected.  When you repot choose a new container that is only an inch or two larger.  If you need to use a large pot for aesthetic reasons simply nest your container in the larger one and water the smaller container that will keep the roots from drowning. A mature citrus can live in a 5 gallon sized pot for many years and my 17-year-old lemon is doing great in a 10-gallon pot.  I re-pot every three years and do very minor root pruning each time. You will want to give plenty of water during its time outside, keep them on the dry side when overwintering indoors.

These plants are heavy feeders during the growing season.  Select a fertilizer labeled for citrus or chose one with a good amount of nitrogen with micronutrients.  I use a combination of Osmocote applied in May and Neptune’s Harvest fish and seaweed fertilizer for its high mineral and amino acid content monthly.  If your plants leaves are yellowing it could be a sign of overwatering, lack of nutrients, or cold damage.  Light colored new growth is normal on Seville oranges and a few others.   Fertilize lightly until March when overwintering.

In autumn before your trees migrate back inside it is important to spray the plants with a product that is effective on spider mites. Some common insecticides actually increase mite populations by killing beneficial insects and stimulating mite growth.  I like to use neem oil based products, make sure you coat both sides of the leaves and small branches when applying. Neem oil is also effective on scale insects, which are the other common pest you need to consider.

Citrus will appreciate the brightest indoor spot you have and remember to mist the leaves daily with water to make up for the low humidity most homes have in winter.

Many unusual citrus are in vogue now, used by inspired chefs and trendy mixologists.  I have always enjoyed these useful and rewarding plants. 

Roger Zinn