Fertilizers and Nutrients

fertilizers and nutrients

Most commercial potting soils and soil-less mixtures are not very rich in nutrients. One way to give your plants a good start is to amend the commercial growing medium with compost, or other organic enrichments available at your garden store, in a ratio of three parts potting mixture to one part compost.

In a pot, you are responsible for providing all of the nutrients your plant needs to grow, so you will need to fertilize and add micro-nutrients on a regular basis. If you do not want to think about fertilizing, it is possible to add slow-release fertilizer pellets to the soil mix. Otherwise, a good quality water-soluble fertilizer should be used from time to time. Choose a “complete” fertilizer that provides the three basic nutrients needed by plants: nitrogen, phosphorus, and potassium. By law, fertilizers list three numbers representing the percentage of each of these nutrients in the mixture; for instance, 20-10-20 would be 20% nitrogen, 10% phosphorus, and 20% potassium. The rest of the fertilizer is filler.

Plants which do not have access to these basic nutrients will not thrive, and you cannot rely on standard potting soils or soil-less mediums to provide them. The main symptoms which may indicate a nutrient deficiency are listed on the next page. Choosing a complete fertilizer will address all of these weaknesses. Apply the fertilizer according to the directions on the package, paying special attention to whether the solution should go on the leaves (foliar fertilizer) or just into the soil. Apply fertilizer in small amounts, regularly, as large quantities of fertilizer have the potential to burn plants and are largely lost through run-off anyway.

Fertilizer and Nutrients

Minor Nutrients

Minor Elements
(Macro Nutrients)
Functional Uses In PlantDeficiency Symptoms
IRON (FE)Formation of chlorophyllInterveinal chlorosis of younger leaves
MANGANESE (MN)Helps in uptake of carbon dioxide which is used for photosynthesis.Mottled interveinal chlorosis of leaves
BORON (B)Development of shoot tips and leaf bud; formation and movement of sugars in plantTip growth die back and deformed buds
CHLORINE (CL)Stimulates photosynthesisWilting but rare because present in water
COPPER (CU)Formation of chlorophyll and converting sunlight into energy; also a fungicideLeaf chlorosis and shoot tip growth die back
MOLYBDENUM (MO)Helps production and use of nitrogenMarginal and interveinal chlorosis of older leaves
ZINC (ZN)Formation of growth hormonesMottled leaf chlorosis, little leaves; Rosetting

Major Nutrients

Major Elements
(Macro Nutrients)
Functional Uses In PlantDeficiency Symptoms
NITROGEN (N)Necessary for growth and development of green leaves and stems; component of most proteinsChlorosis (yellowing) of older, lower leaves; stunting
PHOSPHORUS (P)Promotes root growth and development; energy storage and transfer within plantPurple like coloration; stunted root growth
POTASSIUM (K)Improves cold hardiness, drought tolerance and disease resistance; promotes bloomsPoor flowering and fruit formation; brown leaf
SULPHUR (S)Component of 3 proteins and 2B vitamins; flavor of onion, garlic, and mustard; a fungicideChlorosis of younger leaves; stunting
CALCIUM (CA)Promotes cell division, strong cell walls, and sturdy structureCollapse of cell walls and structural failure; curled
leaf tips; stunting
MAGNESIUM (MG)Component of chlorophyll; essential for photosynthesisMarginal (edges) and interveinal (between veins) chlorosis of older leaves

Plant Specific Nutrients

Plant TypeNutrients NeededSome Recommended Fertilizers
BEDDING OUT PLANTSHigh phosphorous to promote flowering.Water soluble powder: Miracle Gro, Plant-Prod Flowering
promote flowering.
Liquid concentrate: Alaska MorBloom
Granular: So-Green Rose and Flower, Smartcote Annual Food
HANGING BASKETSTreat as a bedding out plant or use slow release fertilizer in the soil.Water soluble/liquid concentrate: see ‘Bedding Out Plants’
Granular: Smartcote Hanging Basket Food
Other: Jobe’s Plant Spikes
High phosphorous for root growth; a root stimulant is often requiredWater soluble: Plant-Prod 10-52-10
Liquid concentrate: Plant Starter 5-15-5 with rooting stimulant
Granular: Bone Meal, Root Grow
VEGETABLESLess emphasis on nitrogen except for leafy vegetables.Water soluble: Plant-Prod Tomato & Vegetable
Liquid concentrate: Schultz Tomato Food
Granular: So-Green Garden Food or Tomato Food, Vigioro Pink
All Purpose
WATER PLANTSOnly trace elements are required.Pond tablets in the water at the rate of one per month will
supply required. the necessary nutrients.
Relatively high phosphorous fertilizer to encourage roots & flowers.Water soluble: Plant-Prod Flowering, Miracle Gro
Granular: Bone Meal
Note: Bloodmeal helps keep some squirrels from feeding on
PERENNIALSNeed phosphorous for a strong root system and potassium for healthy growth.Water soluble: Plant-Prod Flowering, Miracle Gro
Liquid concentrate: Alaska MorBloom, Shultz All Purpose
Granular: Bonemeal, So-Green Perennial Food, Smarcote
Perennial, Miracle Gro Shake-n-Feed
TRANSPLANTINGHigh phosphorous to promote root
Water soluble: Plant-Prod 10-52-10
Liquid concentrate: Plant Starter 5-15-5 with rooting
Granular:Root Grow or Bone Meal, So-Green Super
VINESRequire higher levels of phosphorous.Water soluble: Miracle Gro, Plant-Prod Flowering
Liquid concentrate: Alaska MorBloom
Granular: So-Green Clematis & Vine, Bone Meal when planting
WINTERIZINGNever add nitrogen in fall as it encourages excess leafy growth.A fertilizer without nitrogen will strengthen plants for better
winter survival: Alaska MorBloom, So-Green Muriate of Potash
FOLIAGE PLANTSA balanced fertilizerWater soluble: Schultz All Purpose, Plant-Prod All Purpose
Liquid concentrate: Schultz All Purpose
Slow release: Jobe’s Houseplant or Fern & Ivy Spikes
FLOWERINGA moderately high phosphorous levelWater soluble: Plant-Prod Flowering
Liquid concentrate: Schultz All Purpose
Slow release: Jobe’s Flowering Plant Spikes, Myke Indoor
AFRICAN VIOLETSRequire phosphorous for bloom
Liquid concentrate: African Violet
ORCHIDSWater soluble: Orchid Food, Plant-Prod Orchid
CACTUSCacti need less nitrogenLiquid concentrate: Cactus Food

how to grow herbs indoors

growing herbs inside

How to Grow Herbs Indoors?

Fragrant and full of taste, herbs are a favorite of gardeners and cooks alike. And you can learn how to grow herbs indoors if you’re new to planting or gardening. It’s super easy! The other beauty of growing herbs indoors is that you can grow them in the dead of winter as long as you have a window or even just a grow light.

how to grow herbs indoor choosing herbs

Choosing Herbs

Before you start growing herbs indoors, get to know the light, soil and water requirements of each of your favorite herbs. While it’s easy growing herbs indoors that flourish, certain herbs such as fennel and horseradish don’t. These herbs require deeper root systems than most containers allow. But luckily many delicious culinary herbs like chives, parsley, basil and rosemary grow happily inside.

how to grow herbs indoor light


Herbs are light-loving plants that require six hours of sunshine each day. Indoor herbs should be placed in a sunny windowsill or near a south-facing window if available. If not, consider supplemental lighting with a grow light. These only cost a couple of dollars at Home Depot, and will make growing herbs indoors in places like basements and attics possible.

How to grow herbs indoors that once lived outside

When moving herbs grown outdoors into your home, be sure to give the herbs time to adapt to less sun-drenched conditions. This can be done by moving plants from full sun into a shadier spot each week. Rosemary is especially sensitive to changes in light conditions because it’s slow-growing and does not acclimate quickly enough to indoor conditions.

how to grow herbs indoor that once lived outside soil and water

Soil and Water

Place herbs in soil that has good drainage. A sterile, soilless mixture containing perlite provides proper drainage, while also limiting the chance of disease and pest problems.

Herbs should be watered when the soil feels dry to the touch. But never let the soil dry out completely. You should see water coming out of the bottom of the pot when you water–this ensures that the pot has not become clogged. Place your pots in a plastic, leak-proof container before watering. And if you’re growing basil, water it at the base. It doesn’t like getting its leaves wet.

How to grow herbs indoors that really flourish:

To maintain the health and vigor of your plants, you can use fertilizers about once every two weeks. Use more than this and your herbs may start tasting like fertilizer–not a flavour you want in your soup!

Want to give your herbs an extra boost? While you’re popping your own multivitamin, why not show your herbs the same courtesy? Liquid seaweed is packed with B1 vitamins, which help the plants grow and produce necessary oils.


A common misconception when people learn how to grow herbs indoors is that they think the herbs are immune to pests. Indoor herbs can be prone to attacks by whiteflies, aphids, spider mites, scale insects and mealy bugs. But don’t despair! It’s much easier to eliminate bug problems in small indoor planters.

Remove bugs by placing the plants under a strong stream of water. You can even use insecticidal soap and still maintain organic standards. Follow the directions on the bottle, and use repeated applications until the problem is eliminated.

You now know the basics on how to grow herbs indoors, so why not give it a try? The mini elevated garden works perfectly for herbs. Just remember that no matter how you’re potting them, make sure you place them near a window. They’ll thank you, and so will your taste buds. Happy planting!